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Transcript
F2 (OIC)
1. AC and DC generators are similar in the sense that
they are ______.
a. Both producing alternating voltages
b. Both control the delivery of voltages
c. Both supply 3 – phase power
d. Constructed at the same size for the same
KW rating
Ans. A
2. A DC shunt generator has its field windings
connected in ______.
a. Series with series windings
b. Parallel with the rheostat
c. Series with armature windings
d. Parallel with the armature windings
Ans. D
3. What will the phase relationship of a six – pole,
three – phase, rotating field generator?
a. 60 degrees
b. 120 degrees
c. 180 degrees
d. 360 degrees
Ans. B
1
4. In an AC generator, direct current from a separate
source is passed through the windings of the rotor
____________.
a. By means of slip rings and brushes
b. By means of commutator
c. By means of rotating bar magnet
d. By means of rotating coil
Ans. A
5. The main purpose of an electric space heater fitted
on large AC generators is to ______________.
a. Keep the unit warm for immediate starting
b. Prevent moisture from accumulating in the
windings during shutdown
c. Prevent windings from getting brittle
d. Prevent dirt from entering the windings
Ans. B
6. One factor that determines the frequency of an
alternator is the _____________.
a. Armature coil of windings
b. Number of magnetic poles
c. Strength of the material used
d. Output current
Ans. B
2
7. The frequency output of an operating alternator is
controlled by the ____________.
a. Speed of the motor poles
b. Armature coil windings
c. Strength of the materials used
d. Output voltage
Ans. A
8. The cycle per second developed by the alternator
aboard ship depends on _____________.
a. Speed of engine driving the alternator
b. Resistance applied to the transformer
c. Speed of the induction motor
d. Voltage regulator output
Ans. A
9. To raise the frequency of an AC generator in
service, the operator should ____________.
a. Increase the feed to the transformer
b. Increase the speed of the diesel engine
driving the AC generator
c. Reduce the load in the system
d. Increase the number of magnetic poles
Ans. B
3
10. The frequency of an AC generator is adjusted by
means of the ______________.
a. Governor control of the diesel engine driving
the AC generator
b. Transformer adjustment
c. Raise or lower load in the system
d. Raise field excitation
Ans. A
11. What will happen to the prime mover of AC
generator if the load is removed?
a. Speed of the engine will increase slightly
then return to original speed
b. Speed of the engine will decrease slightly
then return to original speed
c. Speed will remain the same
d. Engine will shut down
Ans. A
12. As load is added to an AC generator, the prime
mover speeds will ______________.
a. Increase
b. Decrease
c. Remain the same
d. None of these choices
Ans. B
4
13. The slowing down of AC generator prime mover
speed every time a load is added will be raised to
original speed by the _______________.
a. Governor
b. Nozzle valve
c. Stop engine
d. Field rheostat
Ans. A
14. When securing an AC generator, you are obliged
to ______________.
a. Reduce the load on the circuit
b. Trip the generator circuit breaker
c. Stop the engine
d. Switch the voltage regulator to “manual”
Ans. A
15. A change in field excitation of an alternator
operating in parallel will bring change to its
___________.
a. Frequency
b. Current output
c. Voltage output
d. Kilowatt load
Ans. C
5
16. A vessel is equipped with two ship’s service
generators. Generator #1 is rated at 900 KW and
the generator #2 is rated at 600 KW. During
parallel operation and a total ship power load of
1,000 KW, the KW load on generator #2 will be
__________________.
a. 100 KW
b. 200 KW
c. 400 KW
d. 600 KW
Ans. C
Given: DG1 = 900 kw
DG1 = 900
X 100% = 60%
DG2 = 600 kw
1,500
Bus load = 1,000 kw
DG2 = 600
Find: DG2 kw load?
1,500 X 100% = 40%
Solution:
Total Load CAP = DG1 + DG2
DG2 Load Shared at 40% of
= 900 kw + 600 kw
1,000 kw bus load
= 1,500 kw
= 1,000 kw x 0.40
Load Sharing % (characteristic)
= 400 kw
17. How is the DC output obtained from a brushless
exciter?
a. Directly from the commutator by induction
b. By the use of ship rings mounted on the
armature
c. By the use of semiconductor rectifier
mounted on the exciter armature
d. By the use of semiconductor rectifier
mounted on the stator
Ans. C
18. Chattering of the slip ring brushes on a generator
maybe remedied by ____________.
a. Brush holders lubrication
b. Re-insulating the brushes
c. Increasing the length of pigtail
d. Cleaning the slip rings
Ans. D
6
19. If an AC generator experience voltage failure, the
cause may be ______________.
a. An open in the field circuit
b. Brushes shifting out of place
c. Rotating slip ring out of contact
d. Excessive locked-rotor current
Ans. A
20. Voltage failure of an AC generator may be
caused by ___________.
a. Failure of the exciter generator
b. A tripped bus circuit breaker
c. High mica segments on the stator bus bar
d. Excessive prime mover speed
Ans. A
21. An alternator will fail to produce line voltage as
result of ____________.
a. Open circuit breaker
b. Exciter generator failure
c. Wrong position of the brushes
d. Worn out slip rings
Ans. B
7
22. Two AC generators of the same capacity are
operating in parallel. One with zero speed droop
setting and the other with 5% speed droop. If its
capacity is not exceeded, the unit that has zero
setting will ____________.
a. Take smaller share of load
b. Have poor power output
c. Have poor power characteristics
d. Maintain the frequency of the system
Ans. D
23. When paralleling two AC generators, the
frequency of the incoming generator prior to
closing its breaker should be___________.
a. Higher than bus frequency
b. Lower than bus frequency
c. Same as bus voltage
d. Slightly higher than bus frequency
Ans. D
24. You are attempting to parallel two AC generators,
and the synchroscope pointer is revolving fast in
the clockwise direction. It means that the incoming
AC generator frequency is _______________.
a. Higher than the bus frequency
b. Lower than the bus frequency
c. Same as bus frequency
d. Much higher than the bus frequency
Ans. D
8
25. The load sharing characteristics of two diesel
generator engines operating in parallel are mostly
dependent on their governor ____________.
a. Speed droop setting
b. Load limit setting
c. Speed limit setting
d. Idle speed setting
Ans. A
26. The diversion of load between two parallel
running generators is determined by the
____________.
a. Characteristics of governors
b. Field excitation of the engines
c. Number of poles in the alternator
d. All of the choices
Ans. A
27. The kilowatt load is evenly distributed between
two alternators just placed in parallel by adjusting
its ______________.
a. Balance flywheel
b. Governor settings
c. Transformer output
d. Field excitation
Ans. B
9
28. Equal load factors on paralleled AC generators
are maintained by an automatic _____________.
a. Voltage regulator
b. Power relay
c. Governor switch
d. Reverse current relay
Ans. A
29. Why is it desirable to operate paralleled AC
generators at the same power factor?
a. Circulating currents are kept to a minimum
b. Field excitation losses are kept to a minimum
c. Generator governors are less likely to hunt
d. All of these choices
Ans. A
30. Attempting to parallel an AC generator that is out
of phase with the bus will result in ___________.
a. A breaker trip
b. KW increase
c. Synchronization lamp damage
d. Non – working power factor
Ans. A
10
31. After closing the circuit breaker to place the two
similar alternators in parallel, the next step is to
balance the _______________.
a. Power factor
b. Voltage load
c. Current load
d. Kilowatt load
Ans. D
32. Two parallel alternators are operating near rated
load. If one trips out mechanically, the operator
should immediately _____________.
a. Restart the tripped machine
b. Switch off all non – essential loads in the
circuit
c. Start the generator
d. All of these choices
Ans. B
33. You are attempting to parallel two AC generators
and the synchroscope pointer is revolving in the
counterclockwise direction. This indicates that the
incoming generator frequency is __________.
a. Higher than bus
b. Lower than bus
c. Same as bus
d. Out of order
Ans. B
11
34. Which of the following problem will occur if the
circuit breaker of the incoming alternator is closed
and it is 180 degrees out of phase with the loaded
alternator?
a. The rotor of the incoming alternator will hunt
b. The rotor of the incoming alternator will stop
c. It could damage the incoming alternator due
to severe cross current
d. Both alternators will be out of phase by 180º
Ans. C
35. When
paralleling
two
alternators,
the
synchroscope pointer approaches 0 degree
position. This indicates that the alternator
frequencies are ______________.
a. 180º out of phase
b. Incoming alternator is in phase with the bus
c. Synchroscope lamps are broken or damaged
d. Incoming alternator is running too fast
Ans. B
36. When
paralleling
two
alternators,
the
synchronizing lamp grows dim. This indicates that
the incoming alternator is _______________.
a. Ready for closing the circuit breaker
b. Voltage is 180º out of phase
c. Synchronization lamp is defective
d. Running too slowly
Ans. A
12
37. The number of complete cycles of AC or voltage
completed
each
second
is
called
the
_____________.
a. Frequency
b. Period
c. Wave length
d. Hour
Ans. A
38. Which of the following statements does not
represent Electromagnetic field intensity factor?
a. The number of turns of wire in the coil
b. The amount of current flowing in the
conductor
c. The ratio of the coil length to the coil
d. The resistance in series with the load
Ans. D
39. When applying the left-hand rule for generators,
your thumb will point to the ___________.
a. Direction of rotation
b. Direction of magnetic flux
c. Direction of current flow
d. Direction of induced voltage
Ans. A
13
40. When applying the left-hand rule for generators,
your forefinger will point to the ___________.
a. Direction of rotation
b. Direction of current flow
c. Direction of magnetic flux
d. Direction of induced voltage
Ans. C
41. When applying the left-hand rule for generators,
your middle finger will point to the ___________.
a. Direction of rotation
b. Direction of current flow
c. Direction of magnetic flux
d. Direction of induced voltage
Ans. B
42. The characteristic of an electrical circuit that
opposes the starting, stopping or changing of
current flow is called a/an ___________.
a. Inductance
b. Capacitance
c. Electromotive force
d. Magnetic field
Ans. A
14
43. This is developed whenever there is relative
motion or action between a magnetic field and a
conductor. It is called __________.
a. Electromotive force
b. Electromagnetic field
c. Current
d. Voltage
Ans. A
44. Which of the following statements will affect the
capacitance value of a capacitor?
a. The area of the plates
b. The distance between the plates
c. The dielectric constant of the material
between the plates
d. The flow of current in the circuit
Ans. D
45. Capacitance
__________.
is
measured
a. Farads
b. Capacitor
c. Henry
d. Electrons
Ans. A
15
in
units
called
46. The following is a device that transfers electrical
energy from one circuit to another by
electromagnetic induction. It is a ___________.
a. Transformer
b. Battery
c. Generator
d. Rectifier
Ans. A
47. The part of a transformer whose function is to
deliver the load received is called the __________.
a. Primary winding
b. Magnetic flux
c. Secondary winding
d. Rectifier
Ans. C
48. The part of a transformer whose function is to
receive power from the electric source is called the
_______.
a. Primary winding
b. Secondary winding
c. Core
d. Enclosure
Ans. A
16
49. The total voltage induce into the secondary
windings of a transformer is determined mainly by
the ratio of the number of turns in the primary to
the number of turns in the secondary and by
the_________
a. Amount of voltage applied to the primary
windings
b. Amount of current applied to the primary
windings
c. Amount of resistance applied to the primary
windings
d. Length of wire in the primary winding
Ans. A
50. Depending on their atomic structure, different
materials have different quantities of free electrons.
Therefore, the various conductors used in electrical
applications have different values of__________.
a. Resistance
b. Sizes
c. Weight
d. Length
Ans. A
51. In electrical circuit, the resistance unit of measure
is specified in ___________.
a. Ohm
b. Farad
c. Volts
d. Watt
Ans. A
17
52. The heat dissipating capability of a resistor is
measured in ______________.
a. Watt
b. Ohm
c. Ohm
d. Ampere
Ans. A
53. Which of the following electronic component
store electrical energy?
a. Capacitor
b. Transistor
c. Resistor
d. Diode
Ans. A
54. Assume that a 208 volt is applied to the
autotransformer and there is a 10.4 resistive load
connected to the secondary winding of the
transformer. The output voltage of the secondary
winding is 104 volts. The load current should be
____________.
a. 10 amperes
b. 1.0 amperes
c. 2.0 amperes
d. 20 amperes
Ans. A
18
55. The direction of rotation of an induction motor
is___________________.
a. Opposites the rotating field direction
b. The same as the direction of the rotating
field
c. Determined by the number of poles
d. Determined by the staggering of the brushes
Ans. B
56. A switchboard for an AC electrical distribution
system will be provided with which of the following
components?
a. Frequency meter
b. Ammeter
c. Voltmeter
d. All of these choices
Ans. D
57. The numbers cells in a 12 – volt lead acid battery
is ____________
a. 3 cells
b. 4 cells
c. 6 cells
d. 12 cells
Ans. C
19
58. An accidental path of low resistance, allowing a
passage of abnormal amount of current is known
as ______________.
a. Open circuit
b. Short circuit
c. Polarized ground
d. Ground reference point
Ans. B
59. Possible phase relationships between voltage
and current in an alternating current circuit include
which if the following conditions?
a. Current and voltage may be in phase
b. Current may lead the voltage
c. Current may lag the voltage
d. All of these choices
Ans. D
60. The part of the shipboard electrical system used
to control the distribution of power to the branch
circuit is the ______________.
a. Bridge control panel
b. Disconnecting links
c. Governor relay box
d. Main switchboard
Ans. D
20
61. Handled phase sequence indicators are useful
when ______________.
a. Preparing to parallel alternators
b. Connecting lighting branch circuits
c. Trouble shooting DC meters
d. Connecting power lines to the ship
Ans. D
62. The open circuit voltage of a fully charged lead –
acid battery cell is _________.
a. 1.5 volts
b. 1.8 volts
c. 2.0 volts
d. 2.3 volts
Ans. C
63. The purpose of a DC generator brushes is
to________________.
a. Neutralize armature reaction
b. Conduct electric current to an outside circuit
c. Convert DC current to AC current
d. Provide excitation to a DC generator
Ans. B
64. Fuses are rated in ________________.
a. Voltage
b. Amperage
c. capacity
d. All of these choices
Ans. D
21
65. The simplest methods of controlling the terminal
voltage of compound wound DC generators are
with a ______________.
a. Hand-operated field rheostat connected in
series with the shunt field circuit
b. Separate exciter in a series with the load
c. Carbon pile regulator in series with the load
d. Balance coil diverting neutral current through
the shunt field
Ans. A
66. In a 15 horse power induction type motor with a
cage rotor, the current required at stand still to
produce starting torque is approximately
_________________.
a. Half the full load current
b. Equal to the full load current
c. Five time the full load current
d. Ten to twenty times
Ans. C
67. Which of the following components are to
assemble a fluorescent lighting system?
a. Lamp
b. Starter
c. Ballast
d. All of these choices
Ans. D
22
68. Motor controllers or starter contacts may become
pitted and welded together if the contact is
____________.
a. Opened under loaded conditions
b. Close slowly with light pressure
c. Opened too quickly and arc
d. Closed quickly with proportionate pressure
Ans. B
69. When placed in a magnetic field, which of the
materials listed will maintain the highest
permeability?
a. Glass
b. Bakelite
c. Soft iron
d. Aluminum
Ans. C
70. The governor control switch of an alternator is
moved to the raise position. These actions will
_________.
a. Raise the no-load speed setting of the
governor
b. Raise the percentage of speed droop
c. Lower the no-load speed setting of the
governor
d. Lower the percentage of speed droop
Ans. A
23
71. Which of the following will happen to the
alternator frequency if the load is removed from a
turbo generator whose governor has 3% speed
droop?
a. It will remain unchanged
b. It will decrease by approximately 3%
c. It will become variable
d. It will increase
Ans. D
72. As a load is added to an Ac generator provided
with constant field excitation, the prime mover
slows down with the effect of _______________.
a. Lowering frequency and lowering generated
voltage
b. Increasing frequency and increasing
generated voltage
c. Increasing frequency and lowering
generated voltage
d. Lowering frequency and increasing
generated voltage
Ans. A
73. The charge of lead –acid battery is checked with
a/an ________________.
a. Manometer
b. Hydrometer
c. Voltmeter
d. Ohmmeter
Ans. B
24
74. The cycles per second developed by the
alternator aboard your vessel is determined by
______.
A. Speed of the engine driving the alternator
B. Resistance applied to the field rheostat
C.Synchronous speed of induction
D.Adjustment made to the voltage regulator
Ans. A
75. When the operating handle of a molded-case
circuit breaker is in the mid-position, it indicated
that the circuit breaker is _____________.
a. On
b. Off
c. Reset
d. Tripped
Ans. D
76. Which of the following listed devices may be
installed on a large diesel – electric alternating
current propulsion circuit breaker is
____________.
a. Temperature detector coils inserted in the
stator slots for measuring stator temperature
b. A CO2 fire extinguisher system
c. Electric space heaters to prevent
condensation of moisture
d. All of these choices
Ans. D
25
77. On AC vessels, which of the following statements
represents the most difficult problem involved in
obtaining a DC potential suitable for use by
computer components?
a. Step – down transformer is always required
b. Vessel vibration affect the voltage source
c. The voltage must be rectified and made
ripple free
d. Rectifiers cannot operate with voltage
regulators
Ans. C
78. The power factor of an AC generator operating
singularly is determined by the ___________.
a. Connected load
b. Prime mover speed
c. Field Excitation
d. Generators rated voltage
Ans. A
79. When the voltage remains constant and the
resistance is increased in a series circuit, the flow
of current _____________.
a. Increases by the square of the original value
b. Increase
c. Remains the same
d. Decreases
Ans. D
26
80. The voltage output of an Ac generator is
accurately controlled by ____________.
a. Changing the sensitivity of the prime mover
to large changes in voltage
b. Varying the reluctance of the air gap
c. Varying the DC exciter voltage
d. Shorting out part of the armature windings
Ans. C
81. Under which of the following conditions will a lead
– acid battery be given a test discharge”?
a. To determine its capacity
b. Whenever a cell cannot be brought within 10
point of full charge specific gravity
c. When one or more cell are found to have
less normal voltage after an equalizing
charge
d. All of these choices
Ans. C
82. A slow continual loss of electrolyte level from one
cell of a storage battery could be due to
__________.
a. A cracked casing
b. Too low charging rate
c. The specific gravity being higher than normal
d. One filler cap installed too tightly
Ans. A
27
83. Nickel cadmium batteries are superior to leadacid batteries at high discharge rates because they
__________.
a. Deliver a large amount of power and can be
recharge in a shorter time
b. Need fewer cells in connected series and
less mounting space
c. Have higher output voltages and require no
maintenance
d. None of these choices
Ans. A
84. When power is restored after a complete power
failure a steering gear pump will_____________.
a. Have to be restored
b. Have to rest
c. Restart automatically
d. Trips its overload relays
Ans. C
85. Basic electric motor action depends
on________________.
a. A conductor rotated with a magnetic field
b. A current carrying conductor placed in a
magnetic field
c. The relative fore of the commutator and
commutating poles
d. The relative force of the armature and inter
poles
Ans. B
28
86. As a load is added to shunt motor, the motor
will____________.
a. Speed up
b. Continue to operate
c. Slow down slightly
d. stop
Ans. C
87. The frequency of an alternator is controlled from
the main switchboard by adjusting the _________.
a. Frequency
b. Voltage regulator
c. Governor control
d. Synchroscope switch
Ans. C
88. In order to take a current reading with a “clampon” ammeter, the instrument jaws______.
a. Should remain open
b. Cannot touch the adjacent conductor
c. Must be fully closed or should remain closed
d. Will act a transformer primary
Ans. C
29
89. When the ship board electrical distribution circuits
are connected in parallel, additional parallel circuits
will cause the total circuit resistance
to_______________.
a. Increase causing a drop in the line current
b. Increase causing a decrease in the line
voltage
c. Decrease causing an increase in the line
voltage
d. Decrease causing an increase in the line
current
Ans. D
90. When the voltage and current developed in an Ac
circuit reach their peak values at the same time,
the power factor is _____________.
a. Lagging
b. Leading
c. Maximum
d. Minimum
Ans. C
30
91. You are attempting to a parallel two AC
generators and the synchroscope pointer stops at
a position other than zero. If you close the circuit
breaker at this moment______________.
a. The incoming machine will accept all the
load
b. The incoming machine will trip out on low
voltage release
c. A hazardous condition will be created by the
cross current between the machines
d. A hazardous condition will be created by the
incoming machine being at a higher
Ans. C
92. What type of electric motor is commonly used to
start small auxiliary diesel engines?
a. Synchronous
b. Series
c. Shunt
d. cage
Ans. B
93. “Dielectric” is/an _______________.
a. Electrical insulator
b. Current flow
c. Good conductor
d. Semiconductor
Ans. A
31
94. A galvanometer is an instrument used to
measure _________________.
a. Thickness of galvanized metal
b. Resistance of electrical wiring insulation
c. Very small amounts of current or voltage
d. Quantity of galvons in an circuit
Ans. C
95. Electrostatic forces in the high voltage circuits
cause indicating instruments to give
_____________.
a. Parallax readings
b. Highly intuitive readings
c. Highly accurate readings
d. Inaccurate readings
Ans. D
96. In an alternating current electrical system, a low
system power factor is a direct sign of
__________.
a. Waste energy
b. Efficient operation
c. A short in the exciter field windings
d. An excessive number of minor system
grounds
Ans. A
32
97. The voltage of a battery is equal to the
_________________.
a. Voltage of single cell times the number of
cells in the series
b. Amperage of single cell times the number of
cells in the series
c. Efficiency of the number of cells times the
resistance
d. Voltage of a single cell times the number of
cell in parallel
Ans. A
98. How many 1.5 volt batteries are required to
supply a load of 12 volts if the batteries are
connected in series?
a. 8
b. 6
c. 12
d. 10
Solution;
12V = 8 pcs.
1.5V
Ans. A
99. How many 1.5volt batteries are required to
supply a load 12 volts if the batteries are
connected parallel?
a. 12
b. 6
c. 3
d. None of these choices
Ans. D
Note; 1.5v batteries cannot supply a load of
12v if it is connected in parallel, because the
33
output voltage is only 1.5v no matter many 1.5v
connected in parallel.
100.
Three 12 volt storage batteries connected in
parallel will give a total voltage of ________.
a. 12 volts
b. 24 volts
c. 36 volts
d. 48 volts
Solution;
VT = V1 = V2 = V3
12V = 12V = 12V = 12V
Note;
Voltage in a Parallel
Circuit never change
Ans. A
101.
On DC generator, where is the pigtail
located?
a. Feather spring
b. Conductors
c. Brush holder
d. Spiral adjusting spring
Ans. C
102.
If a DC generator was rotated in the wrong
direction, it would fail to come up to voltage
because the _______________.
a. Armature field would oppose the field current
b. Generator would burn out
c. Brushes would burn out
d. Circuit breaker would not energize
Ans. A
34
103.
A generator operates on the principles
that_________________.
a. When the field revolves, current is generated
b. When an armature revolves, a magnetic field
is induced
c. Voltage is induced when a conductor cuts a
magnetic field
d. A small voltage in the primary high voltage
because of the large number of coils in the
secondary
Ans. C
104.
Frequency of an operating alternator is
controlled by the_______________.
a. Relative speed of the rotor poles
b. Number of turns of wire in the armature coil
c. Strength of the materials
d. Output voltage
Ans. A
105.
The line voltage generated by an alternator
is adjusted by varying the___________.
a. Prime mover speed
b. Equalizer bus
c. Excitation voltage
d. Residual magnetism of the shield
Ans. C
35
106.
The voltage of an operated AC turbo
generator is raised or lowered by adjusting the
__________.
a. Generator field exciter
b. Phase sequence switch
c. Generator governor controls
d. Synchronizing switch
Ans. A
107.
What is overall result of increasing the load
on the secondary of a transformer?
a. Decrease in the primary current
b. Decrease in the primary voltage
c. Increase in the primary voltage
d. Increase the primary current
Ans. D
108.
In DC circuits, power is expressed as the
product of ________________.
a. Volts and amperes
b. Ohms and amperes
c. Volts and coulombs
d. Amperes and coulombs
Ans. A
36
109.
A horse magnet has ______________.
a. 2 poles
b. 3 poles
c. 4 poles
d. 1 pole
Ans. A
110.
Retentivity is the power a metal has
retained_______________.
a. The current in a circuit
b. Magnetic lines force
c. Electron plow within the circuit
d. Electricity when moving at high speeds
Ans. B
111.
How many cells are there in a 12 – volt
battery?
a. 6
b. 4
c. 2
d. 8
Ans. A
112.
If the specific gravity of a 12 – volt battery at
80oF is 1.225, the battery is _________.
a. Dead
b. Fully charged
37
c. Shorted
d. Partially charged
Ans. D
113.
Counter electromotive force is measured in
______________.
a. Volts
b. Ohms
c. Amperes
d. Coulombs
Ans. A
114.
Which of the following expression correctly
states Ohms law?
a. Volts equal amperes times resistance
b. Amperes equals to volts divided by
resistance
c. Resistance equals volts divided by amperes
d. All of these choices
Ans. D
115.
In a parallel circuit, which of the following is
the same throughout the circuit?
a. Impedance
b. Current
c. Voltage
d. Resistance
Ans. C
38
116.
When using Ohms law, V divided by R would
solve for________________.
a. Amperage
b. Voltage
c. Resistance
d. Watts
Ans. A
117.
When using Ohm’s law, V divided by I would
solve for___________________.
a. Amperage
b. Voltage
c. Resistance
d. Watts
Ans. C
118.
Volts times amperes
equals______________.
a. Kilowatts
b. Watts
c. Ohms
d. Watts - hours
Ans. B
119.
The unit of electrical force is the ________.
a. Volt
b. Amperes
c. Watts
39
d. Ohm
Ans. A
120.
Electrically operated safety devices on
auxiliary diesel engines functions to stop the
engine by_____________.
a. Shutting off fuel supply
b. Shutting off air supply
c. Shutting off cooling water supply
d. Shutting off lube oil
Ans. A
121.
Before starting an electric motor after a long
stoppage, the operator shall ensure that is
___________.
a. Dust – free
b. Dry
c. Moving freely by hand
d. Wet
Ans. A
122.
The insulation resistance of an electric of an
electric motor is measured by___________.
a. Voltmeter
b. Megger
c. Ammeter
d. Ampere meter
Ans. B
40
123.
Your contact resistance – to – ground is
substantially reduce when you step on a
__________.
a. Wet floor
b. Humid floor
c. Dry floor
d. None of these choices
Ans. A
Note;
The bodies resistance is greatly reduced when
wet. Insulation resistance decreases
when wet or with the presence of
moisture.
124.
Battery rooms must be adequately ventilated
to___________.
a. Dissipate explosive gases
b. Keep room cool
c. Supply fresh air
d. Protect equipment
Ans. A
125.
The electrolyte in a lead - acid storage
battery consists of distilled water and
_______________.
a. Electrochloric acid
b. Sulfuric acid
c. Hydrochloric acid
d. Muriatic acid
41
Ans. B
126.
A fuse will blow when the current
flow_____________.
a. Exceeds the rated value
b. Remove from the equipment
c. Cause the fuse to overheat
d. Increase suddenly
Ans. A
127.
Etched or burned marks on the brushes
contact surfaces could be caused by__________.
a. Wrong alignment of brushes
b. High rotation of rotor
c. High rotation of rotor
d. Brushes improperly positioned
Ans. D
128.
In order to comply with the class regulation,
the main switchboard onboard modern ships shall
have_______________.
a. No sharp objects exposed
b. No live parts exposed
c. Protection covers
d. All of these choices
Ans. B
42
129.
Most of the switchboards main bare parts
are insulated with______________.
a. Synthetic resin
b. Plastic film
c. Rubber paint
d. None of the above
Ans. A
130.
The purpose of a main switchboard reverse
power trip is to ___________.
a. Prevent main circuit overload
b. Prevent circuit breaker coil from being
damage
c. Prevent alternator motorization
d. Prevent blackout
Ans. C
131.
The purpose of the reverse power relay is to
trip the circuit in case of _________-.
a. Main circuit overload
b. Circuit breaker coil from blowout
c. Alternator motorization
d. Blackout
Ans. C
43
132.
A generator is prevented from being
motorizes by the use of a/an________________.
a. Over speed trip
b. Reverse power relay
c. Back pressure trip
d. Over current trip
Ans. B
133.
A bus disconnect link is used to
isolate________________
a. One bus from another
b. The generator circuit from the bus
c. Other circuits from main switchboards
d. Defective alternator
Ans. B
134.
A switchboard for an AC electrical system
requires the use of which device?
a. Frequency meter
b. Ohmmeter
c. Induction voltage regulator
d. Current transformer governor
Ans. A
44
135.
The grounded neutral conductor of a three –
wire feeder, in dual voltage 220/110 volt DC
switchboard should be _______________.
a. Left unprotected for excess current
b. Protect with a 115 amp link fuse
c. Protect with a 220 amp link fuse
d. None of these choices
Ans. A
136.
The part of the new electrical system that
controls the power distribution to the branch circuit
is called________________.
a. Bridge control panel
b. Main switchboard
c. 440/220v feeder panel
d. Starter panel
Ans. B
137.
Equipment with temporarily wiring
arrangements in cabins, engine rooms and other
locations onboard is called________________.
a. Unauthorized electrical equipment
b. Personal electrical equipment
c. Ship’s property
d. None of these choices
Ans. A
45
138.
All switchboards and distribution system
must be examined in accordance with _________.
a. Company’s preventive maintenance system
b. Maker’s recommendation
c. Chief engineer’s order
d. All of these choices
Ans. D
139.
Periodical insulation test shall be carried out
within the intervals specified in _______.
a. Chief engineer order book
b. Manufacturer’s instruction book
c. Ship’s record book
d. Preventive maintenance system
Ans. D
140.
When passing through restricted waters,
such as Panama Canal, Suez Canal or rivers, or in
condition of heavy weather it is prudent to use
____________.
a. Two generators in parallel
b. Three engine watch keepers
c. Slow down the engine
d. The pilot services
Ans. A
141.
To ensure that it is ready in case of
emergency and for the efficient operation of the
46
emergency generator the engine shall be started
once every ______________.
a. Week
b. Month
c. Semi-annually
d. Two weeks
Ans. A
142.
The on – load of emergency generator /
alternator must be carried out must be carried out
at least every _________.
a. Week
b. Month
c. Semi-annually
d. Two weeks
Ans. A
Note; Ship above 500 GRT
143.
All tests done on shipboard emergency
components should be entered into the___.
a. Engine log book
b. Bell book
c. Electrician’s record book
d. Chief engineer’s record book
Ans. A
144.
To ensure that the emergency generator is
always ready for immediately use, its associated
47
component below shall be kept fully charge at all
times.
a. Main starting air bottle
b. Emergency starting air bottle
c. Emergency hydraulic tank
d. Auxiliary starting air bottle
Ans. B
145.
For maintenance of non-sealed batteries,
below statements are TRUE except
____________.
a. Only the correct electrolytes are to be used
b. Cells are regularly inspected and topped up
as necessary
c. Use only pure distilled water for topping up
d. It should be placed in a tightly closed
compartment
Ans. D
146.
For “maintenance – free” batteries, which
one statement below is NOT TRUE?
a. Only correct electrolytes are to be used
b. Cells are regularly inspected and topped up
as necessary
c. Use only tap water
d. Use only sulfuric acid
Ans. C
48
147.
To protect the radiators of emergency
generator sets located external to the main
machinery space from very cold weather it must be
filled with__________.
a. Alcohol
b. Distilled water
c. Anti – freeze solution
d. Anti – boil solution
Ans. C
148.
All electrical equipment in potentially
hazardous atmosphere must be certified as
_________.
a. Intrinsically safe equipment
b. Fool proof equipment
c. Tamper proof equipment
d. Long lasting equipment
Ans. A
149.
Before insulation testing is to be done on
equipment in hazardous location, the area
concerned must be certified as__________.
a. Gas free
b. Well - ventilated
c. Ready for use
d. Ready for entry
Ans. A
150.
Which of the following is NOT considered
part of shipboard safety equipment?
a. Emergency alarm system
49
b. Fire detection system
c. Gas detection system
d. Engineer call system
Ans. D
151.
The cold storage room for meat shall be
maintained at _______________.
a. – 18oC or better
b. – 12 or better
c. – 8oC or better
d. – 4oC or better
Ans. A
152.
The vegetable room temperature shall be
maintained as near to as:
a. – 2oC
b. 0oC
c. +2oC
d. +5oC
Ans. D
153.
When using electric arc equipment,
whenever it is necessary for additional leads to
extend the range of operation only correct grade of
cable shall be fitted with approved_________.
a. Weather proof connectors
b. Fully insulated leads
50
c. Cables wires
d. None of these choices
Ans. A
154.
During welding and similar operation, the
welder must wear protective clothing such as, but
not limited to ___________.
a. Welding apron
b. Safety shoes
c. Safety helmet
d. All of these choices
Ans. D
155.
Goggles and welding masks are worn to
protect the welder from ___________.
a. Sun rays
b. Sparks
c. Heat
d. Strong wind
Ans. B
156.
On Ships designated for UMS operation, the
engineer on watch must be satisfied that this/ these
equipment is / are in good working order before
leaving the engine room.
a. Automatic controls
b. Alarm system
51
c. Fire detection system
d. All of these choices
Ans. D
157.
The fire detection system covering any
space shall be kept activated except _____.
a. Authorized hot work is taking place
b. Testing the system
c. Cooking is going on
d. It is necessary to isolate the system
Ans. A
158.
Before shutting down the fire detection
system, who shall give prior approval?
a. Officer on watch
b. Engineer on watch
c. Chief engineer
d. Master
Ans. D
159.
Who is the person responsible for the safe,
efficient operation and maintenance of the vessel’s
electrical system including but not restricted to
____________.
a. Chief engineer
b. Designated electrical officer
c. Engineer on duty
52
d. Master
Ans. D
160.
As per USCG 33 CFR 164.35, the vessel is
not permitted to be operated in US waters unless it
has onboard and in properly operating condition
_______________.
a. Two radars
b. Evaporating plant
c. Sewage plant
d. Oil bilge separator
Ans. A
161.
Electric shock is often accompanied by
falling, which may cause additional physical injury
and required__________.
a. Hospitalization
b. First aid action
c. Emergency treatment
d. All of these choices
Ans. B
53
162.
Which of the following statements is correct
when you are in contact with a live wire having a 1
ma current?
a. Usually harmless but will produce a slight
tingling sensation or involuntary movement
b. Result in loss of muscle control. This can
result in an ability to let go of the energy
source, thus increasing the degree of injury
c. Enough to result in death
d. Can cause internal organ damage and
internal burns. Cardiac arrest and respiratory
failure may occur.
Ans. A
163.
Which of the following statements is correct
when you get in contact with a live wire having a 5
– 10 ma current?
a. Usually harmless but will produce a slightly
tingling sensation or involuntary movement
b. Result in loss of muscle control. This can
result in an ability to let go of the energy
source, thus increasing the degree of injury
c. Enough current to result in death
d. Can cause internal organ damage and
internal burns. Cardiac arrest and
respiratory failure may occur.
Ans. B
54
164.
Which of the following statements is correct
when you get in contact with a live wire having a 75
– 300 ma current?
a. Usually harmless but will produce a slightly
tingling sensation or involuntary movement
b. Result in loss of muscle control. This can
result in an ability to let go of the energy
source, thus increasing the degree of injury
c. Enough current to result in death
d. Can cause internal organ damage and
internal burns. Cardiac arrest and
respiratory failure may occur.
Ans. C
165.
Which of the following statements is correct
when you get in contact with a live wire having 2
amp and above current?
a. Usually harmless but will produce a slightly
tingling sensation or involuntary movement
b. Result in loss of muscle control. This can
result in an ability to let go of the energy
source, thus increasing the degree of injury
c. Enough current to result in death
d. Can cause internal organ damage and
internal burns. Cardiac arrest and
respiratory failure may occur.
Ans. D
55
166.
Which of the following is recommended for
the rescue and care of shock victim?
a. Remove the victim from contact at once
b. De – energize the affected circuit and use
only non – conductor object to drag or push
the victim to safety
c. Touch a shock victim who is still in contact
with energized circuit
d. All of these choices
Ans. B
167.
One of the easiest ways to create a static
charge is ______________.
a. By friction
b. By lighting
c. By applying heat
d. By applying electricity
Ans. A
168.
If transformer are being worked on or
inspected, which of the following rules shall apply?
a. Remove the transformer from all power
source in the primary and secondary circuit
b. Removed all the fuses from the power
source
c. Trip the circuit breaker and take action to
prevent their accidental resetting
d. All of these choices
Ans. D
56
169.
A breakable mercury filled thermometer
should not be used in a lead acid battery to
measure the electrolyte temperature as an
accidental breakup can cause __________.
a. Severe sparkling and explosion
b. Rapid oxidation of the battery plate
c. Violent gassing at the positive plates
d. Corrosion in the battery terminals
Ans. A
170.
Flame scanner as used with boiler
combustion control system to monitor flame quality
and to:
a. Shut off the fuel supply of flame is detected
b. Occur fuel service pimp in the event of floor
fire
c. Serviced the forced draft fan in the event of
flame failure
d. Regulate the fuel air ration for more efficient
combustion
Ans. A
171.
In addition to monitoring flame quality, flame
scanners are used in combustion
a. Stop the fuel from entering the burner upon
detect of flame failure
b. Secure the force draft in case of flame failure
c. Automatically stop the fuel service pump
d. Adjust fuel / air ratio for non efficient
combustion
Ans. A
57
172.
Which of the following represents a limitation
to be aware of when the boiler auto combustion
control is operated in “hand mode”?
a. Boiler safety interlocks are by-passed
b. Burner is not capable of full capacity firing
rate
c. Flame failure is deactivated
d. Solenoid valves remain in auto mode
Ans. A
173.
An over speed trip serves to
______________.
a. Stop the engine by cutting off air supply
b. Stop the engine by cutting off fuel supply
c. Stop the engine by cutting off cooling water
supply
d. Slow the engine but not stopping it
Ans. B
174.
An over speed trip stops the diesel engine
when the engine
a. Runs out of fuel
b. Exceeds the set maximum speed
c. Has high cooling temp
d. Has high exhaust temperature
Ans. B
58
175.
The over speeding of the diesel engine
diving an electric generated could cause
_________.
a. Damage to windings
b. Reverse poser to trip
c. Over current to trip
d. Excessive exhaust temperature
Ans. A
176.
The over speed device installed in some
engines is automatically actuated by______.
a. Expiry force
b. Solenoid
c. Hydraulic pressure
d. Centrifugal force
Ans. D
177.
An electric tachometer receives the engine
speed signal from a _________.
a. Small generator mounted as engine
b. Bimetallic sensing device
c. Slip ring activated
d. Stroboscopic sensing device
Ans. A
59
178.
Another device that detects engine speed is
the ________.
a. Speed pick-ups mounted at the engine
flywheel
b. Grounding system slip rings
c. Laser light system mounted on the propeller
shaft
d. Electric governor
Ans. A
179.
When a fluorescent lamp has reached the
end of its useful life, it should be replaced
immediately on the resulting flashing
may_________.
a. Blow the lamp’s circuit breaker
b. Explode, causing glass to fly in all directions
c. Short circuit the ballast transformer
d. Damage the starter and the ballast
Ans. D
180.
Alternating current circuits developed
resistance, capacitance and voltage; the
capacitance of capacitor is expressed in ______.
a. Ohm
b. Henry
c. Mho
d. Farad
Ans. D
60
181.
Current flowing only in one direction is called
___________.
a. Alternating current
b. Omni directional current
c. Direct current
d. Sinusoidal current
Ans. C
182.
Electric motors intended for use outside the
engine room and boiler are frequently rated at a
designated ambient temp. of 40C. What is the
equivalent in Fahrenheit?
a. 52oF
b. 104oF
c. 72oF
d. 129.6oF
Ans. B
183.
The rated temperature rise of electric
motors is the __________.
a. Average temperature at any given latitude
b. Temperature rise above ambient
temperature at rated load
c. Temperature rise to resistance above 10
overload
d. Permissible difference in the ambient
temperature of the motor due to existing
weather conditions
Ans. B
61
184.
Capacitance is the property of an electric
circuit that resists or opposes amp charge of the
_____.
a. Current in the circuit
b. Voltage in the circuit
c. Inductance in the circuit
d. Resistance in the circuit
Ans. B
185.
Ambient temperature is the
______________________.
a. Normal operating temperature, less the room
temperature
b. Temperature of the room where the motor
is located
c. Amount of temperature rise developed by an
operating motor
d. Temperature of the outside air
Ans. B
186.
A circuit which a fuse has blown would be
categorized as a / an _____________.
a. Short circuit
b. Open circuit
c. Bonded circuit
d. Grounded circuit
Ans. B
62
187.
A circuit is a considered an open circuit
when ____________.
a. A fuse blown
b. It is not in use
c. Te supply is in “off” position
d. All of these choices
Ans. D
188.
Electric circuits are protected against
overloads and short circuits by means of a/an
_________.
a. Circuit breaker
b. Amplifier
c. Diode
d. Capacitor
Ans. A
189.
Incandescent lamps are classified according
to _______________.
a. Shape and type of service
b. Size and style of base
c. Operating voltage
d. All of these choices
Ans. D
63
190.
The cross-sectional area of a shipboard
electrical cable as expressed on ________.
a. Millimeter
b. Number gage
c. Centimeter
d. Circular mills
Ans. D
191.
When electrical cables generated watertight
bulkheads _________.
a. They should be grounded on either side of
the bulkheads
b. They must be bent to radius of six diameters
c. A watertight stuffing tube capable of
accepting packing should be employed
d. They should be secured by clamp
Ans. C
192.
All electrical cables passing through
watertight bulkheads must be __________.
a. Installed with watertight tubes
b. Grounded a both sides of the bulkhead
c. Welded on both sides of the bulkhead
d. Fitted with unions on each side of the
bulkhead
Ans. A
64
193.
Copper is often used as an electrical
conductor because of ____.
a. Has high resistance at low temperature
b. Has a highly polished surface
c. Has good conductivity
d. Holds insulation together well
Ans. C
194.
Electric cables are formed of stranded wires
to ________.
a. Increase the current carrying capacity for a
given size wire
b. Increase their flexibility
c. Decrease the weight of the wire
d. Assure good conductivity at bend points
Ans. B
195.
Which of the following characteristics is most
critical in determining the size of the cable to be
used in a particular circuit?
a. Voltage rating
b. Weight per unit length
c. Current rating
d. Inductance for unit length
Ans. C
65
196.
The electrical energy necessary to power an
emergency sound power telephone small vibrating
bell obtained from _________.
a. Emergency batteries from the general alarm
b. Each station’s hand-cranked generator
c. Emergency switchboard
d. Normal 115/220V power supply
Ans. B
197.
The electrical energy necessary to transmit a
person’s voice air an emergency sound powered
telephone circuit is obtained from:
a. Dry cell batteries
b. Ship service switchboard
c. Emergency switchboard
d. Speaker’s voice
Ans. D
198.
The purpose of an impressed current
cathodic system aboard ship is to ____.
a. Prevent corrosion of the hull propeller,
rudder and line shafting
b. Neutralize the vessel’s stray magnetic fields
which would interfere with radar
c. Protect the engine room and deck machinery
from oxidation and salty air
d. Maintain cleanliness of superstructure
Ans. A
66
199.
For more complete vessel protection when
using an impressed current cathodic system
________.
a. All ship’s alternators have temperature
sensing device installed
b. Straps connected at the propeller shaft and
grounded through a ship ring/brush
arrangements
c. Hull’s magnetic field is aligned with true
north
d. Machinery on deck and engine room is
coated with zinc chromate
Ans. B
200.
In an impressed current cathodic protection
system the anode is _________.
a. Connected to the hull and deteriorates with
tie
b. Insulated from the hull and does not waste
away
c. Connected to the hull last does not waste
away
d. Insulated from the hull but deteriorates with
time
Ans. B
67
201.
Impressed current cathodic protection is
used on vessels instead of ________.
a. Fire alarm system
b. Repeated painting
c. Sacrificial zincs
d. Vacuum tube degaussing system
Ans. C
202.
Automatic voltage regulators provided a
switch board functions to ___________.
a. Regulate to AC load on the generator
b. Protect the switchboard from high voltage
c. Govern prime mover speed to control
voltage
d. Vary the field excitation to the generators
Ans. D
203.
In cold weather, the specific gravity of a
battery __________.
a. Rises
b. Lowers
c. Remains the same
d. None of these choices
Ans. A
68
204.
If the emergency switchboard pilot light is
“ON” it means __________.
a. The generator is on line
b. The power is available from the generator
c. The generator is in parallel with the bus
generator
d. Pilot exciter is malfunctioning
Ans. B
205.
Under voltage trips are frequently on
switchboard circuits breakers to trip _______.
a. Out the generator in the event of severe
arching or sparkling
b. Out the generator when there is a reversal of
power
c. Out the generator when there is a low
voltage in the main circuit
d. The breaker of the generator over speed by
5%
Ans. C
69
206.
The most common type of AC service
generator found aboard ship is the stationary
__________.
a. Electromagnetic field, revolving armature
type
b. Electromagnetic field, oscillator armature
type
c. Armature, oscillatory electromagnetic field
type
d. Armature, rotating electromagnetic field type
Ans. D
207.
Brushless AC generators are designed to
operate without the use of _________.
a. Brushes
b. Slip rings
c. Commutators
d. All of these choices
Ans. D
208.
Voltage generated by most AC generators is
fed from the machine to the bus by means of
____________.
a. Brushes on a commentator
b. Brushes on a ship rings
c. Ship rings on a commentator
d. Direct connection from the stator
Ans. D
70
209.
The frequency of an AC generator is
adjusted by means of the ________.
a. Main alternator field rheostat
b. Exciter field rheostat
c. Prime mover governor control
d. Equalizing reactor
Ans. C
210.
H2SO means ______________
a. Sulphuric acid
b. Hydrochloric Acid
c. Hydraulic Acid
d. Muriatic
Ans. A
211.
One important difference between Y –
connected and Delta connected generators is that
delta connections have_____________.
a. Line voltages equal to the vector sum of the
phase voltages
b. Phase voltage 90 out of sync
c. Line current equal to the phase current
d. Line voltage equal to the phase voltage
Ans. D
71
212.
It is a good practice to have the frequency of
the incoming alternator adjusted slightly higher
than that of the bus frequency because
_________.
a. This allows the oncoming-machine to accept
load immediately
b. This prevent the machine from floating on
the line
c. The reverse power relay is prevented from
activating
d. All of these choices
Ans. D
213.
If two AC generators have been placed in
paralleled, the three power load is initially
distributed evenly by _______________.
a. Balance oil
b. Changing field excitation
c. Adjusting the generator control settings
d. Rheostat
Ans. C
214.
The KW load can be adjusted on parallel
generators by using the ___________.
a. Balance coil
b. Rheostat
c. Field excitation
d. Governor control
Ans. D
72
215.
If the field excitation is suddenly lost as
alternator operating in parallel, that alternator will
__________.
a. Supply excessive current in the bus
b. Operate at the same load
c. Lose its load and end to over speed
d. Become overloaded and stop
Ans. C
216.
When two AC generators are being
paralleled, the breaker should be closed with the
Synchroscope pointer rotating in the
______________.
a. Slow, clockwise direction, just before 12
o’clock position
b. Fast, clockwise direction, just after 12 o’clock
position
c. Slow, counter clockwise direction after 12
o’clock position
d. Fast, counter clockwise direction after 12
o’clock position
Ans. A
217.
When parallel, AC generators must have the
same _________.
a. Frequency
b. Number of phases
c. Phase rotation
d. All of these choices
Ans. D
73
218.
When paralleling two alternators, the
synchronizing lamps remain lit as the
synchroscope pointer approaches “0”. This
indicates the _________.
a. Incoming alternator is running too last
b. Alternator voltages are 180 apart
c. Synchroscope is defective or broken
d. Alternator power are in phase
Ans. C
219.
When paralleling two alternators using three
synchronizing lamps, the flicking of all three lamps
progressively slower and slower. This means the
___________.
a. Frequency of the incoming generator is
approaching that of the bus
b. Frequency of the incoming generator is less
than that of the bus
c. Phase rotation of the incoming alternators is
opposite that of the bus
d. Terminal voltage of the incoming alternator is
approaching that of the bus
Ans. A
220.
Motorizing of an alternator is undesirable
_____________
a. Alternator will be damaged
b. It puts additional load on the bus
c. High voltage pulses are induce in the bus
d. All of these choices
Ans. B
74
221.
When shore power is being connected to a
ship in dry-docks __________.
a. The ship generator are parallel with shore
power to provide continuous power
b. Proper phase sequence must be established
c. Exactly 450V must be supplied from shore
d. Exactly 60Hz must be provided by the
terminal
Ans. B
222.
When two generators are on the line and are
sharing the load equally they are said to be
operating in ______________.
a. Frequency
b. Series
c. Parallel
d. Resonance
Ans. C
223.
The primary function of an electric motor is
to ________.
a. Develop torque
b. Generate high voltage
c. Produce a magnetic field
d. Generate high electrical resistance
Ans. A
75
224.
Any electric motor can be constructed to be
_____________.
a. Short proof
b. Ground proof
c. Explosion proof
d. Over load proof
Ans. C
225.
An advantage of DC motors over AC motors
is that they ____________.
a. Are less expensive
b. Require less maintenance
c. Can be started across the line
d. Offers an effective means of controlling the
speed
Ans. D
226.
The direction of rotation of a DC motors can
be reverse by ______________.
a. Reversing the field connection
b. Reversing the armature connections
c. Wiring the field and armature in parallel
d. Wiring the field and armature in series
Ans. A
76
227.
Uneven area of the commutator surface on
direct current generators can be caused by
___________.
a. Rapid change is load
b. Excessive operation at light load
c. In correct position of brush
d. Unequal pole spacing
Ans. C
228.
In general, DC motor brush sparkling can be
caused by ___________.
a. Incorrect brush grade, pressure or position
b. Poor brush grade
c. Uneven commutator height
d. Over speeding motor
Ans. A
229.
When is it necessary to renew brushes in a
DC motor?
a. The whole set be replaced
b. Only those worn out more than 50% need to
be changed
c. Only chipped or brittle units need to be
replaced
d. Lubricate the contact surfaces of brushes
Ans. A
77
230.
The torque produced by a motor when its
shaft will not turn even through rated voltage is
applied to the stator is known as ____________.
a. Locked rotor torque
b. Pullout torque
c. Breakdown torque
d. Torque margin
Ans. A
231.
An operating characteristic appearing on the
name plate of shipboard AC motor is
______________.
a. Type of winding
b. Input kW
c. Temperature rise
d. Locked rotor torque
Ans. C
232.
The operator of electrical motors keep a
constant check on ____________.
a. Low loads necessities frequent cleaning
b. Exceeding nameplate values shortens useful
life
c. Energy is wasted if full loading is not utilized
d. Power factor correction methods are load
dependent
Ans. B
78
233.
When testing a three circuit electric motor for
uses condition, the motor should be stopped
because ___________.
a. Testing an un-energized circuit presents a
hazard to the testing personnel
b. A faulty fuse can go undetected with the
motor energized
c. Reversed polarity of the circuit would be
indicated by the voltage tester with the circuit
energized
d. All of these choices
Ans. B
234.
Discoloration of the motor bars in a squirrelcage motor is typical evidence of _______.
a. Moisture
b. Overheating
c. Vibration
d. All of these choices
Ans. B
235.
The rotation of a three-phase induction
motor can be reverse by _______.
a. Interchanging any two of the three line leads
to the starter
b. Disconnecting any three line leads to the
starter
c. Switching the shunt field cool leads
d. Permanently disconnecting any two of the
three line leads to the stator
Ans. A
79
236.
If a single phase induction motor fails to
start, the problem maybe _______.
a. An open in the main winding
b. A shorted shunt field
c. A closed centrifugal switch
d. Low voltage input
Ans. A
237.
A machine that converts mechanical energy
into electrical energy by using the principle of
magnetic induction is called a ____________.
a. Generator
b. Pump
c. Turbine
d. Motor
Ans. A
238.
Which of the following is NOT classified as a
DC Generator according to their excitation
methods?
a. Series wound
b. Shunt wound
c. Compound wound
d. Squirrel – cage wound
Ans. D
80
239.
When the current load is more than can be
carried by a single generator, the problem may be
solved by ___________.
a. Paralleling two more generators
b. Reducing the load
c. Increasing the speed of prime mover
d. All of these choices
Ans. A
240.
When precise speed control and varying
load are needed, you should use a/an ________.
a. Alternating current generator
b. Direct current generator
c. Electronic motor
d. Electric motor
Ans. B
241.
In general, the COST of an AC motor as
compare to DC motor is that an Ac motor costs
_______________.
a. Less
b. More
c. Same
d. Slightly more
Ans. A
81
242.
The key for the rotor an AC motors to run in
both synchronous and induction type motor is that
their stators must have a/an__________.
a. Rotating magnetic field
b. Electric source
c. Rotating torque
d. All of these choices
Ans. A
243.
The type of Ac motor employed on washing
machines, refrigerator, compressors, bunch
grinders and pumps is often a/an_____________.
a. Induction motor
b. Synchronous motor
c. DC motor
d. Single phase motor
Ans. A
244.
Amortisseur windings are installed in a
synchronous motor to __________.
a. Reduce eddy current losses
b. Produces a higher power factor
c. Provides a means for starting
d. Eliminate arcing, between the stator the
motor
Ans. C
82
245.
The multiple prefix “giga” (G) means
_________.
a. Thousand (10 to the 3rd power)
b. Million (10 to the 6th power)
c. Billion (10 to the 9th power)
d. Trillion (10 to the 12th power)
Ans. C
246.
The multiple prefix “kilo” means ________.
a. Thousand (10 to the 3rd power)
b. Million (10 to the 6th power)
c. Billion (10 to the 9th power)
d. Trillion (10 to the 12th power)
Ans. A
247.
A motor controller contains three selector
push buttons labeled “start”, “jog”, and “stop”.
When the “jog” button is pushed, the motors
__________.
a. Will run continuously after the “jog” button is
released
b. Will run until the “jog” button is released
c. Will not start until both the “jog” and “start”
buttons are pushed
d. Will not start unless the “stop” button is
pushed
Ans. B
83
248.
A “dead front” switch board is one
_____________.
a. Without switches on it
b. With insulated switches and no exposed
terminals
c. Without circuit breaker
d. Without safely handrails nor rubber mats
Ans. B
249.
When charging 100 amp hour lead – acid
battery ______.
a. The temperature of the electrolyte should not
be allowed to exceed 90oF
b. The charging rate should be no greater than
125% of the battery amp-hour rating
c. The source of power charging should be 2.5
volts per cells
d. Gassing within the battery decreases when
nearing full and it will be necessary to reduce
charging current to a law finishing rate.
Ans. C
250.
When lead – acid batteries are charging,
they always give off hydrogen gas that is
__________
a. Considered inert
b. Highly explosive
c. Extremely toxic
d. Heavier than air
Ans. B
84
251.
The specific gravity of the electrolyte in a
lead – acid battery is measured _____.
a. Gould plate
b. Titration plate
c. Hydrometer
d. Litmus paper test
Ans. C
252.
Which of the following activities occurs
during the charging process of a lead – acid
storage battery?
a. The specific gravity of the acid increases
b. Both plates change chemically to lead
sulfate
c. The specific gravity of the acid decreases
d. Hydrogen gas is absorbed
Ans. A
253.
Which of the following devices are protected
from being motorized by a reverse-power relay?
a. Alternator
b. Wave guides
c. Exciters
d. Amplidynes
Ans. A
85
254.
When a lead-acid battery begins gassing
freely while receiving a normal charge, the
charging current should ____________.
a. Be increased
b. Remain unchanged
c. Be decrease
d. Shut off
Ans. C
255.
An ammeter reads slightly above “zero”
when its leads are disconnected, this a result of
____________.
a. Mechanical misalignment of the meter points
b. A poor ground for the meter case
c. Static electricity in the air
d. Resistor inside the meter storing charges
Ans. A
256.
When an alternator is to remain idle for even
a few days ___________.
a. Lift the brushes and disconnect the pigtails
b. Insulate the collector rings with strips of
cardboard
c. energize the heater circuit
d. Energize the exciter circuit
Ans. C
86
257.
Proper storage battery maintenance includes
_______________.
a. Keeping connections tight and casing
surfaces clean
b. Making sure electrolyte level is below the
separator plates
c. Insulating the terminals with naval jelly
d. Maintaining a high charging rate at all ties
Ans. A
258.
Part of the insulation of practically all
electrical machinery is in the form of organic
compounds which contain some amount of
______________.
a. Asbestos
b. Water
c. Fiber
d. Plastic
Ans. C
259.
Due to the operating characteristics of the
system, time lag fuses (or dual-element fuses) are
necessary for use in _______________
a. Main lighting circuits
b. Motor starting circuits
c. Emergency lighting circuits
d. General alarm circuits
Ans. B
87
260.
Which of the following materials is a good
electrical insulator?
a. Wood
b. Silver
c. Copper
d. Gold
Ans. A
261.
The plates of a NiCad storage battery are
made of ______________.
a. Potassium hydroxide with a small amount of
sulfuric acid
b. Lead and lead peroxide
c. Silver oxide and lead sulfate
d. Combinations of nickel powder and nickel
and cadmium salts
Ans. D
262.
Routine maintenance of ship’s service
alternator should include _____________.
a. Changing the pedestal bearing insulation
yearly
b. Megger testing of all rectifying diodes
c. Lubricating excitation slip rings
d. Periodic cleaning of the air filters or screens
Ans. D
88
263.
Nickel –cadmium storage batteries are
superior to lead-acid batteries because they
_________________.
a. Put out higher voltages and require no
maintenance
b. Can remain idle and keep a full charge for a
long time
c. Need fewer cells in series and use less
mounting space
d. All of these choices
Ans. B
264.
Which of the listed ranges represents
specific gravity corrected for temperature for the
electrolyte of a fully charge portable lead-acid
battery?
a. 1.100 to 1.150
b. 1.180 to 1.200
c. 1.280 to 1.300
d. 1.750 to 2.000
Ans. C
265.
The state of charge of a lead-acid battery is
best indicated by the ___________.
a. Individual cell voltage
b. Ampere-hour capacity
c. Electrolyte specific gravity
d. Total cell voltage
Ans. C
89
266.
To test fuses in an energized circuit, you
should used a _______.
a. Low voltage light bulb
b. Megohmmeter
c. Voltmeter
d. Resistance meter
Ans. C
267.
The main engine auxiliary blower shall be in
this position in order to change – over engine
control from engine control room ____________.
a. Manual
b. Auto
c. Remote
d. Service
Note;
Change-over from ECR
to Bridge Control
Ans. B
268.
When engine starting is under control, the
starting air feed is halted every time engine
revolution reaches _____________.
a. Dead slow ahead
b. Cut – off setting
c. Fuel is supplied
d. Engine running in fuel
Ans. B
90
269.
Every time the auto acceleration and auto
deceleration device for main engine for main
engine rpm are in service in a vessel fitted with
engine speed control program, they are indicated
in the control console by _______________.
a. “Program in progress “ lamp is “on”
b. “Program in auto “ lamp is “on”
c. “Program running” lamp is “on”
d. “Program running in remote control “ lamp is
“on”
Ans. A
270.
The engine speed acceleration or speed
deceleration program at the bridge control console
is cancelled ____________.
a. By pressing the program by-pass button
b. By moving Telegraph handle to a different
position
c. By moving the telegraph handle to
maneuvering speed
d. By doing any of these choices
Ans. D
271.
The rpm of the main engine can do no longer
be raised when it reached the below preset limit
a. RPM limit
b. Speed limit
c. Over speed
d. Governor limit
Ans. A
91
272.
To avoid the main engine from being
exposed to a prolonged harmful vibrations during
maneuvering, a quick RPM passage device is fitted
to keep the engine RPM at _____________.
a. Below or above the critical speed limit
b. Within the critical speed limit
c. Operator’s speed option
d. Maker’s speed option
Ans. A
273.
The engine starting fuel setting of the
governor is usually set at _____________.
a. Dead slow ahead
b. Slow ahead
c. Half ahead
d. None of these choices
Ans. D
274.
Starting of main engine cannot be started
due to interlocking device such as _______.
a. Turning gear safety device
b. Fuel cut – off device
c. Emergency trip device
d. All of these choices
Ans. D
92
275.
Starting of main engine cannot be made
when this condition is reached.
a. Telegraph lever in “stop” position
b. Starting air pressure is at alarm point
c. Telegraph lever in ahead/astern position
d. All of these choices
Ans. D
276.
The main engine speed can be gradually
accelerated from full maneuvering speed to full
navigation speed by using the
_________________.
a. Load program
b. Telegraph handle
c. Governor control
d. Fuel handle
Ans. A
277.
The main engine speed can be gradually
reduce from navigation full speed to maneuvering
speed by using the ____________.
a. Load program
b. Telegraph handle
c. Governor control
d. Fuel handle
Ans. A
93
278.
When the main engine fails to start, the
telegraph lever shall be placed at this position
before a second starting can be effected.
a. Stop
b. Run
c. Ahead
d. Astern
Ans. A
279.
During normal engine speed (navigation full
speed) condition, the fuel can be cut-off
instantaneously by pressing the _____________.
a. Emergency trip button
b. Main engine trip button
c. Manual trip button
d. All of these choices
Ans. B
280.
The main engine fuel supply will be
automatically cut-off when this condition is
reached.
a. Over speed
b. Main lube oil low. Low pressure
c. Camshaft lube oil low, low pressure
d. All of these choices
Ans. D
94
281. Main engine will automatically slow down when
this condition is reached.
a. Main engine lube oil pressure low
b. Crankcase oil mist density high
c. Camshaft lube oil low
d. Exhaust gas temperature low
Ans. B
282.
If the engine is running at the direction
opposite of the telegraph transmitter command,
this alarm is activated.
a. Wrong Speed
b. Wrong direction
c. Wrong way
d. Wrong position
Ans. C
283.
The alarms in the engine control system are
in “repose” when the telegraph is at this position.
a. Finish with engine
b. Standby engine
c. Bridge control
d. Engine control
Ans. A
95
284.
The equipment that provides the monitoring
and printing of transmitter positions, date and time,
whenever the telegraph transmitter position is
changed is called _________.
a. Telegraph logger
b. Telegraph printer
c. Transmitter position logger
d. None of these choices
Ans. A
285.
What color appears to warn the user that the
paper needs to be renewed when the amount of
thermal paper in the longer reaches near the end?
a. Blue
b. Red
c. Yellow
d. Brown
Ans. B
286.
Which of the following main engine safety
device is NOT a start interlock device?
a. Fuel cut – off
b. M/E trip in operational
c. Turning gear disengage
d. Control air low
Ans. D
96
287.
The bridge control simulation safety device
test can only be affected when the main engine is
at this position.
a. Stop
b. Ahead
c. Astern
d. None of these
Ans. A
288.
In a NAVCO type bridge control system, the
speed control of the main engine is not executable
from the bridge control console when the electric
signal to this device is not normal.
a. Electric governor
b. Electric telegraph
c. Electric control console
d. Electric actuator
Ans. A
289.
At extremely low temperatures, a
semiconductor is basically an _____________
a. Conductor
b. Insulator
c. Electron
d. Element
Ans. B
97
290.
An electron has a ____________.
a. Negative charge
b. Positive charge
C. Neutral charge
D. No charge
Ans. A
291.
The resistance of a semiconductor material
compared to the resistance of ceramic or glass
material is:
a. More
b. Less
c. Equal
d. None of these choices
Ans. B
292.
The three most common semiconductor
devices are:
a. Transistor, diodes, ic
b. Transistor, pcb, relays
c. Transistor, diodes, capacitors
d. Transistor, diodes, relay
Ans. C
98
293.
The cargo pump turbine of generator over
speed relay initiates closing of the throttle valve
when an excessive centrifugal force or speed
causes:
a. Spring loads weight to trip a valve hatch
b. Spring loaded fly balls actuate a control lever
c. Oiled pump develops pressure to open a
spring loaded relay valve
d. Lube oil control temperature actuates a
solenoids valve
Ans. C
294.
The over speed tripping device installed on
an auxiliary turbine is automatically actuated by
_______________.
a. Applied spring force
b. Hydraulic pressure
c. High back pressure
d. Centrifugal force
Ans. D
295.
The governor of turbo generator maintains
constant speed by oil flow pressure and directly
changing the position of governor.
a. Throttle valve
b. Lever
c. Steam chest
d. Back pressure
Ans. B
99
296.
Constant speed governors are normally
employed with _____________.
a. Generator engines
b. Turbines
c. Electric motors
d. Main engines
Ans. A
297.
The steady frequency of an alternator
attached to a generator engine is maintained by:
a. Throttle control mechanism
b. Governor with variable speed control
c. Governor/nozzle control valve
d. Constant speed governor
Ans. C
298.
When a ship service generator equipped
with centrifugal type hydraulic governor load
increases, that action will occur in the governor
internal mechanism.
a. Weight will more inward
b. Lifting will have inward
c. Pilot valve pushing into the cylinder
d. Oil is pumped into the cylinder
Ans. C
100
299.
If two generator will the same no load speed
setting are operated in a parallel, the unit that has
lesser speed drop will ___________.
a. Get less load
b. Get larger share of a load
c. Have poor speed control
d. Have poor power response
Ans. B
300.
The portion of the engine speed control has
manual positioning but with automatic indexing can
be found in a ____________.
a. Rheostat
b. Governor
c. Hand wheel
d. Engine telegraph
Ans. D
301.
When cargo turbine’s governor malfunctions
affecting the speed of the unit you should
_____________.
a. Shutdown the turbine
b. Locate the problem
c. Make entry into log book
d. All of these choices
Ans. A
101
302.
When will be back pressure trip occur in a
cargo pump turbine?
a. Oil pressure is too low
b. Discharge pressure of pump to high
c. Gland leak off is too high
d. Exhaust pressure rises above preset limit
Ans. D
303.
The main throttle valve on a turbine admits
steam directly into the _________________.
a. Steam chest
b. Nozzles
c. Blades
d. Shaft
Ans. A
304.
In a diesel engine governor, a mechanical or
hydraulic action preventing the overcorrection of
the fuel supply is called ______________.
a. Stability
b. Hunting
c. Compensation
d. Sensitivity
Ans. C
102
305.
Rotating flyweights acting against a spring
force will provide a simple type of ________.
a. Feed water regulator
b. Governor
c. Safety valve
d. Control valve
Ans. B
306.
A pilot valve and servomotor in a governor
are used to __________.
a. Create hunting
b. Open fuel or steam valve
c. Increase speed
d. Reduce speed
Ans. B
307.
A constant speed governor is usually
installed on a ________.
a. Generator engine
b. Cargo pump
c. Electric motor
d. Wheelhouse
Ans. A
103
308.
In any governor, there is a small range of
speed in which no corrective action occurs. This
range is called the governor dead band and is
caused by ________.
a. Friction in the governor linkage
b. Excessively sensitivity
c. Compensation adjustment
d. Hydraulic pressure
Ans. A
309.
The fuel injection pumps on a diesel engine
are controlled by a linkage system attached to the
____________.
a. Governor
b. Fuel injector
c. Camshaft
d. Crankshaft
Ans. A
310.
Irregular engine speed of a diesel generator
engine can be caused by ______.
a. High generator load
b. Poor fuel viscosity
c. Poor fuel injectors
d. Big clearance in the fuel linkage
Ans. D
104
311.
If diesel start but failed to reach normal
speed, the cause maybe _________.
a. Insufficient fuel supply
b. Faulty governor
c. Improper fuel pump timing
d. All of these choices
Ans. D
312.
A large, low speed main propulsion diesel
engine is operating at rated load and speed while
the vessel is in a calm sea. As the sea waves
increases, the engine governor maintains the same
RPM but the load indicator will show ________.
a. Increase in load
b. Decrease in load
c. Load remains the same
d. None of these choices
Ans. A
313.
When a vessel encounters rough seas but
the main propulsion diesel engine is steel set to run
at normal load, the operator shall immediately take
this action.
a. Increase the load limit setting
b. Decrease the load limit setting
c. Increase engine RPM
d. Ignore the situation
Ans. B
105
314.
The ability of the governor to prevent
fluctuations in engine speed is called ________.
a. Sensitivity
b. Stability
c. Promptness
d. Speed droop
Ans. B
315.
What device used to limit engine torque at
various engine speed?
a. Speed limiting governor
b. Variable speed governor
c. Constant speed governor
d. Load limiting governor
Ans. D
316.
A change in engine speed is required before
a governor is able to make corrective movement of
fuel rack. This aspect of governing is commonly
expressed as a percent and is known as
__________.
a. Governor sensitivity
b. Governor promptness
c. Speed droop
d. Isochronous governing
Ans. A
106
317.
The device that most commonly utilizes the
principle of electromagnetic induction is the
_________.
A. Diode
B. Transformer
C. Transistor
D. Rheostat
Ans. B
318.
In addition to monitory flame quality, flame
scanner are used in combustion ____.
A. Stop the fuel from interring the burner upon
detect of flame failure
B. Secure the force draft in case of flame failure
C. Automatically stop the fuel service pump
D. Adjust fuel/air ratio for non efficient
combustion
Ans. A
319. When testing of electrical component on wet
metal flat form, what safety precautions you must do?
Ans. Use rubber matting
320.
What is the frequency of FM Radio?
Ans. 88.1 to 107.9 MHz
107
321. If transformer will be connected to a DC source,
the transformer will overload at the __________.
A. contacts
B. secondary coil
C.core
D.primary winding/coil
Ans. D
322.
Step-down transformer;
A. voltage and current will both be increased
B. voltage decrease as current increases
C.voltage and current will both be decreased
D.voltage increases as current decreases
Ans. B
323.
Step-up transformer;
A. voltage and current will both be decreased
B. voltage and current will both be increased
C.voltage increase as current decreases
D.voltage decreases as current increases
Ans. C
324. A device with high input voltage and delivers low
output voltage is __________?
A. step-up transformer
B. primary transformer
C.step-down transformer
D.secondary transformer
Ans. C
108
325. A device with low input voltage and delivers high
output voltage is _______?
A. primary transformer
B. secondary transformer
C.step-down transformer
D.step-up transformer
Ans. D
326. A transformer that uses a single winding for
voltage transformation?
A. Step-up transformer
B. Step-down transformer
C.Auto-transformer
D.Isolation transformer
Ans. C
327.
An open coil in a transformer is indicated by?
A. ‘Zero’ resistance accompanied by high
inductance
B. No resistance accompanied by stray
inductance
C.Infinite resistance in addition to normal
inductance
D.Infinite resistance and no inductance
Ans. D
328. When servicing a battery with electrolyte, be sure
to ___________.
Ans. wear protection
109
329. Shape of governor gear coupling attached to a
high speed/range engine is _________.
Ans. cone shape
330.
Frequency of A.M. radio __________.
Ans. Amplitude modulation or Low band
frequency (kilo hertz)
331. Four lamps are connected in parallel in a single
circuit. If one of the lamp burns out, the others will
__________.
A. all go out
B. become dimmer
C.burn with original intensity
D.become brighter
Ans. C
332. To properly seat the brush on slip rings you
should ___________.
A. sand paper
B. crocus cloth
C.emery cloth
D.all of the above
Ans. A
110
333. Which of the following materials is recommended
for finishing the slip rings after grinding or turning?
A. Grade 00 sand paper
B. Canvas wiper
C.Crocus cloth
D.Smooth file
Ans. C
334. The most practical method used for resurfacing a
ship’s service motor commutator is to _______.
A. turn it down in the ship’s lathe
B. use a grinding rig
C.use a hand stone
D.burnish it with commutator stones
Ans. B
335. For routine cleaning of commutator, you should
apply _______.
A. course sand paper in a slow back and forth
motion across the commutator slots
B. an emery cloth parallel to the axis of the
machine
C.a canvas wiper to the machine while running
D.cotton swabs between the commutator bars
Ans. C
111
336. A full wave rectifier has one diode burned out in
an open condition. What will be the output
characteristic of the device?
A. Zero
B. Half-wave rectified
C.Full-wave rectified
D.Equal to AC input
Ans. B
337. One diode of a full wave rectifier has burned out
in a shorted condition. Therefore, the output will be
________.
A. zero
B. half-wave rectified
C.full-wave rectified
D.equal to AC input
Ans. D
338. Sound pressure is measured in decibels (d13).
The healthy human ear can hear frequencies ranging
from ________.
A. 20-20,000 Hz
B. 100,000-200,000 Hz
C.200,000 Hz = 1 MHz
D.1 MHz-20 MHz
Ans. A
112
339.
Compressed air should not be used to clean
motor controller because ____________.
a. it may force metallic particles into coil
insulation
b. the air blast dries out insulation quickly
c. the air mask and respirator would be
required
Ans. A
340.
The removal of paint from electrical
equipment, such as generator, should cautiously
undertaken because ________________.
a. the paint dust is composed of abrasive and
semi-conducting materials which impair
insulation
b. the mechanical shock of paint removal
lessens the dielectric strength of the
insulation
c. paint dust build up has a tendency to cause
corrosion
d. phase windings frequently become isolated
from each other due to dust interference at
the terminals
Ans. A
113
341.
Before working on an electric cargo winch
master switch or controller, you should ______.
a. open the circuit breaker in the power supply
and tag
b. spray the gasket surface with solvent
c. drain condensate from the box
d. heat the switch box to remove any moisture
Ans. A
342.
Which of the following statements represents
the FIRST precaution to be taken prior to working
on any installed electrical component.
a. open the supply circuits and tag the switch
b. wear rubber gloves and boots
c. use only approved non-conducting tools
d. ground the case of the machine before
beginning any repair
Ans. A
343.
Before any work on electronic and electrical
equipment is performed, which of the following
precaution should be carried out _____________.
a. secure and tag the supply circuit breaker in
the open position
b. de-energize the applicable switchboard bus.
c. By-pass the interlock
d. Station a man at the circuit supply switch
Ans. A
114
344.
Capacitors are used on the output of the
power supply in today’s console to _________.
a. filter out ripples
b. prevent overloads
c. act as a permanent load
d. decrease the average value of the output
voltage
Ans. A
345.
Which of the spaces listed in defined as a
location requiring an exceptional degree of
protection when considering the installation of
shipboard electrical equipment?
a. machinery spaces
b. chart room
c. console room
d. accommodation space
Ans. A
346.
Which of the listed precaution should be
taken when cleaning the internal of a motor with
compressed AIR.
a. open the machine with both ends so as to
allow the air and dust to escape
b. be certain that the circuit breaker is open
and tagged on the feeder panel
c. be certain that the air is clean and dry as
possible
d. all of the above
Ans. D
115
347.
Which of the following represent the
accepted method of cleaning dust and foreign
particles from electrical equipment while limiting
damage to electric component.
a. using a vacuum cleaner to remove debris
from the component
b. carefully wiping off the component with a soft
cotton rag
c. blowing a high velocity stream of
compressed air rapidly across the
component
d. using carbon tetrachloride as a cleaning
solvent to clean the components
Ans. A
348.
Which of the following electric motor would
be the safest and most reliable to use on the main
deck of a vessel in foul weather condition.
a. seal motor
b. drip proof motor
c. enclosed motor
d. watertight motor
Ans. D
116
349.
In addition to testing the calibration of a
circuit breaker, maintenance should include all of
the following EXCEPT _______.
a. changing out of magnetic and thermal
heaters yearly
b. checking for corrosion, accumulation of dirt
and thermal fatigue
c. inspecting for loose or missing parts
d. making sure foreign matter does not block
tripping element
Ans. A
350.
When maintenance personnel are working
on electrical equipment, all supply switches should
be secure in the open position and tagged specially
by the ___________.
a. watch engineer
b. chief engineer or first engineer
c. chief electrician
d. person performing the repair
Ans. D
351.
What is the approximate voltage produced
by a NICKEL- CADMIUM battery cell.
a. 1.25v
b. 1.5v
c. 2.20v
d. 6.05v
Ans. A
117
352. A diesel driven emergency generator is
prevented from being parallel with the ship’s service
generators by ________.
a. an electrical interlock system
b. an automatic paralleling trip switch
c. the synchronizing oscilloscope
d. the reverse current relay
Ans. A
353. The air gap provided in induction motors should
be checked periodically with a feeler gage to detect
an unequal air gap and _________.
a. decreased motor magnetizing current
b. hysteresis losses
c. increased power factor
d. mechanical damage to the rotor
Ans. D
354. Which of the following problems is indicated if a
lead acid battery begins to gas violently when it is first
placed on charge?
a. insufficient compartment ventilation is being
provided
b. a short circuit exists in one of the battery
cells
c. the battery is undergoing its normal charging
rate
d. an excessive charging rate is being applied
to the battery
Ans. D
118
355. Complete maintenance of electric motors should
include periodic check for machine __________.
a. Vibration
b. Water tight integrity
c. Speed droop
d. Reactive power
Ans. A
356. Which of the listed fire extinguishing agents
would be suitable for use on an oil fire (Class B), but
dangerous on an electrical fire?
a. Co2
b. Water fog / spray
c. Halon
d. Dry chemical
Ans. B
357.
Which of the following causes electric static
forces?
a. Shampooing
b. Rubbing
c. Exercise
Ans. B
119
358. Regarding battery charging room’s ventilation
should be provided __________.
a. At the lowest points of the room
b. Horizontally near the batteries
c. At the highest point of the room
d. Only when charging is in progress
Ans. C
359. Two 100 watt light bulbs are connected in parallel
across a 100 volt power supply. The total power
developed in the circuit is __________.
a. 200 watts
b. 100 watts
c. 50 watts
d. equal to the product of the amperes times the
voltage in each branch
Ans. A
Solution:
PT = P1 + P2
PT = 100 w + 100 w
= 200 w
360. Which substance listed should be applied to
battery terminals to help prevent corrosion?
a. Zinc chromate
b. Lead hydroxide
c. Naval jelly
d. Petroleum jelly
Ans. D
120
361.
When a lead acid battery explodes, what is
the direction of explosion?
a. Side ways
b. Upwards/top
c. Downward
d. In all direction
Ans. B
362.
Prior to starting an AC generator prime
mover, the voltage regulator cutout switch should
be placed in the ________.
a. manual position
b. bus neutral position
c. raise voltage position
d. transfer position
Ans. A
363.
Automatic voltage regulators functions to
________.
I – Compensate the current
II – Compensate the voltage
III – Filter out ripples
a. I only
b. II only
c. III only
121
d. I, II & III
Ans. D
364.
Atoms with equal/same numbers of electrons
and protons is referred to as ________.
a. equal
b. balance
c. neutral
d. unbalance
Ans. C
365.
A circuit breaker for a 300 kw alternator is
rated at 470 amperes of full continuous load. The
amount of overcurrent allowed is 125%. Which of
the following conditions will trip the breaker?
a. Sustained current flow of 470 amperes
b. Sustained current flow of 500 amperes for 10
minutes
c. Momentary starting load of 550 amperes
d. Sustained current flow of 590 amperes
Ans. D
366. After rubbing a glass rod and fur, it will become
_______.
a. heated
b. electrified
c. fused together
d. no reaction
Ans. B
122
367. What electrical component that covers the
junction box, fuse box, switch box etc?
a. Circuit breaker
b. Power supply
c. Cover
d. Capacitor
Ans. B
368. Which of the following statement is true regarding
electric receptacle outlets?
a. Sufficient number of receptacle outlets in the
crew accommodation for an adequate level of
habitability
b. Each receptacle outlet must be compatible with
the voltage and current of the circuit
c. A receptacle outlet must not have any exposed
live parts
d. All of the above
Ans. D
369. Which of the following statements is/are true
regarding requirements for receptacle outlets aboard
vessels?
a. Each receptacle outlet operating at 100 volts or
more just have a grounding pole
b. Outlets connecting a lifeboat and the vessel
electrical system must have threaded plug
123
c. Machinery space must contain sufficient outlets
for lighting all machinery with a portable light
having a 50 ft flexible cord
d. All of the above
Ans. A
370.
An ohmmeter can be used to measure _______.
A. current flow in circuit
B. voltage between two points in a circuit
C.circuit continuity
D.power
Ans. C
371. Increasing the load on an engine equipped with a
constant speed mechanical governor, will cause the
engine speed to initially ________.
A. increase
B. decrease
C.fluctuate
D.remain constant
Ans. B
372. Which of the listed sections of an emergency
switchboard is used to supply power for alarm signals
under emergency conditions?
A. The generator and bus transfer section
B. The 450 volt, 60 cycle, 3 phase bus
C.The 120 volt, 3 phase, 60 cycle bus
D.The 24 volt DC bus
Ans. D
124
373. Grease coatings on electrical contact surfaces
increase contact resistance and should be removed
with a/an _______.
A. small wire brush
B. compressed air jet
C.clean dry cloth
D.10% solution carbon solvent and water
Ans. C
374. If a transformer is connected to a DC source, the
transformer will overload at the _______.
A. contacts
B. primary coil
C.secondary coil
D.core
Ans. B
375. In a 60 Hz AC system, the current will pass
through one completes cycle in __________.
a. 60 seconds
b. 6 seconds
c. 7 seconds
d. 0.016 second
Ans. D
125
376. The mica used in the commulators of DC
machinery is _________.
a. harder than copper
b. softer than copper
c. the same hardness the copper
d. softer than copper but wears away at a slower
rate
Ans. A
377. Voltage will always
________________.
lead
current
in
a/an
a. capacitive circuit
b. inductive circuit
c. magnetic circuit
d. resistive circuit
Ans. B
378. A burned-out “LED” should be indicated by
_______________.
a. Excessive output
b. A slight glow in the crystal
c. Excessive illumination
d. No illumination
Ans. D
126
379. When discharging fuses and the spring clips are
found to have lost their grip, they should be replaced
or _______________.
a. tightened firmly with insulated pliers
b. clip clamps should be used
c. wired closed with uninsulated varnished copper
wire
d. carefully bent back to their original shapes
Ans. B
380. A shore circuit breaker should be closed only
___________.
a. when the ship’s generators have been directly
paralleled to those on shore
b. when the ship’s generator have been removed
from the bus
c. exactly 450 volts must be supplied from the shore
d. exactly 60Hz must be provided by the terminal
Ans. B
381. The instantaneous reduction in voltage of an AC
generator, resulting from an increase in load and prior
to the automatic voltage regulator correcting the
situation, is called voltage _______________.
a. droop
b. drop
c. dip
d. regulation
127
Ans. C
382. In a hollow glass or clean plastic cylinder – type
fuse design the glass or clear plastic case allows a
visual check if the fuse is_________?
a. Blown
b. Clean
c. Dirty
d. Charge
Ans. A
383. In a rectifier with capacitor , the current though
the load is supplied by the capacitor when the diode
is_________?
A . Cut – off
B. “On”
C. Neutral
D. None of these choices
Ans. C
384. USCG Regulation 46 CRF require the emergency
lighting and power system__?
a. Must be tested under load from emergency
generator before sailing
b. Must be tested & inspected weekly & the date
recorder
c. Batteries must be tested annually & he date
recorded
d. Must be capable of sustaining the emergency
load for 48 hours
128
Ans. B
385. When working on electrical circuits containing
large capacitors, in addition to de- energizing the
circuit , which of the listed precautions should also
taken?
a. Ground the capacitor terminals
b. Check capacitor circuit polarity
c. Keep all radio equipment away
d. Measure capacitor insulation resistance
Ans. A
386. If both “high level” and “ low level” alarms come
on the same address of a centralized control console ,
the most likely problem is a/an------?
a. Failed alarm
b. Extremely low level
c. Sensor failure
d. Extremely high level
Ans. C
387.
The output of a rectifier is a ________?
a. Pulsating DC current
b. Pulsating signal current
c. Pulsating DC voltage
d. Pulsating DC ampere
Ans. B
129
388.
Defects in wiring permit current to jump from
one wire to another before the intended path has
been completed are called______.
a. grounds
b. shorts
c. break
d. open
Ans. B
389.
In an unmanned main engine, an engine
failure occurs. An audible alarm is indicated or
located in the_____________.
I - at each station
II - C/E cabin
III - Navigating bridge
A. I, II & III
B. I only
C.II only
D.III only
Ans. A
390.
Magnetic fluxes are lines of force of the
magnet that travel from_____.
A. North to South pole
B. south to North pole
C. Positive to Negative bodies
D. Negative to positive bodies
Ans. A
130
391.
Whenever an atom losses an electron (-)
charge and has an overall positive (+) charge, it
became______.
A. cation
B. anion
C.anode
D.cathode
OR
A. positive ion
B. lighter
C. moves faster
D. moves slower
Ans. A
392.
Who operate the machine____.
A. Fitter
B. Chief Engineer
C.Master
D.Operator
Ans. D
393.
As a result of a mechanical malfunction in
one of the ships service generators operating in
parallel , you must secure that generator. In order
to prevent a possible overload, to the remaining
generator, which of the following sequential
courses of action should be taken _________.
A. Trip all non-vital distribution feeder circuit
breakers , the malfunctioning generator’s circuit
breaker, & the prime mover throttle trip
131
B. Trip the malfunctioning generators circuit breaker
and prime mover throttle trip.
C.Trip the malfunctioning generator’s circuit breaker
and distribution feeder circuit breakers
Ans. A
394.
Non-adjustable molded case circuit breakers
and classified by frame size, ampere rating and
interruption capacity. The frame size is expressed
in______.
A. Degree centigrade
B. Circular mills
C. Amperes
D. Volts
Ans. C
395.
D/C motor & generator commutator is made
of ________.
A. Copper segments insulated from each other with
hardened mica
B. Copper Segments insulated with soft mica
Ans. A
396.
Time delayed or delayed action fuses are
designed to_______.
A. prevent ground in branch circuit
B. prevent an open in motor circuit
C.permit momentary overload without melting
D.guard lighting & electric circuit
Ans. C
132
397.
Which of the listed procedures is the best
way to tell if a motor become overload?
A. Measure the current flow & compare it with the
motor full load current flow as shown on the
nameplate
B. Feel the motor & judge by the temperature
C.Watch for signs of smoke coming from the motor
D.If the installation is properly designed, there is no
cause for overload
Ans. A
398.
Which of the listed faults cannot be
eliminated, EXCEPT by turning or grinding a
commutator with a rigidly supported tool?
A. Sparking brushes
B. Eccentricity
C. High mica
D. Blackened commutator
Ans. B
399. The most inefficient method of voltage reduction,
from the standpoint of power loss, even when placed
in series with the load, is the use of a/an __________.
A. Resistor
B. Inductor
C. Capacitor
D. Transistor
Ans. A
133
400. A spring-loaded centrifugal flyweight governor
response to reduced engine load with an immediate
increase ________.
A. pilot valve oil pressure
B. speeder spring force
C. compensation needle valve clearance
D. centrifugal force on the flyweight
Ans. D
401.
One circular mil is ________.
A. 1/10 inch
B. 1/1000 inch
C. 1/100 inch
D. 1/100,000 inch
Ans. B
402.
One mil is _________.
A. 0.10 inch
B. 0.01 inch
C. 0.001 inch
D. 1.000 inch
Ans. C
134
403. Which of the following represents a
characteristics of an UNGROUNDED electrical
distribution system?
A. Accidental contact between one line and ground
des not cause an outage
B. Double ground faults on different phases will not
cause an outage
C.Ground detection system are unnecessary
D.Accidental contact between one line and ground will
always cause an outage
Ans. A
404. When securing the AC generator, you should
FIRST.
A. Open the generator circuit breaker
B. Switch to voltage regulator to “manual”
C.Decrease the field excitation to minimum
D.Reduce the load on the unit
Ans. D
405. The purpose of UNDER VOLTAGE protection
device is to _________.
A. prevent high armature current when power is
restored
B. start the motor at a very low voltage
C. trip the load off the motor in case of fire
D. protect personnel from low voltage shock
Ans. A
135
406. A low-voltage protection circuit is used in electric
motor starting equipment to __________.
A. allow the motor to restart automatically on
restoration of voltage without manually
reseating
B. prevent the motor from re-starting
automatically on restoration of voltage
Ans. B
407. Inductance is the property of an electric circuit that
_________.
A. Opposes any change in the applied voltage
B. Opposes any change in the currents flow
through the circuit
Ans. B
408. As a general rule, the first trouble-shooting action
to be taken in checking faulty electric control device is
to ___________.
A. draw a one line diagram of the circuitry
B. test all fuses and measure the line voltage
C. take megger reading
D. insulate the apparatus from ground
Ans. B
136
409. Varying the FREQUENCY OF TURBO
GENERATOR by means of adjusting the _________.
A. generator exciter field
B. governor control
Ans. B
410. A delayed-action fused is most frequently used in
which of the listed circuit ____.
A. lighting circuit
B. motor circuit
C. electric heater circuit
D. radar circuit
Ans. B
411.
When the insulating breaks down within a
metal encased, portable, electric tool ______?
A. Line voltage may be place in the tool casing
making it dangerous to operate
B. You should stand on a grounded deck plate
before energizing the tool
Ans. A
412.
When trouble shooting an alkaline storage
battery, a weak or dead cell is best located by____.
a. Checking the specific gravity of each cell
b. Visually inspecting each cell’s electrolyte level
c. Testing each cell with a VOLTMETER
d. Measuring the electrolyte temperature with
accurate mercury thermometer
137
ANS. C
413.
If the SPEEDER SPRING of the main
propulsion diesel engine GOVERNOR BREAKS
while operating at full-load, the engine RPM
will______.
a. Increase until the overspeed trip actuated
b. Hunt until stabilized by the droop rod
c. Decrease to a slightly lower value
d. Remain the same until manually changed
ANS. C
414.
To prevent interference between the various
radio and TV station, each station is assigned its
own frequency. AM broadcast stations operates at
frequencies in the range of_________.
a. 535 kHz to 1605 kHz
b. 25 kHz to 135 kHz
ANS. A
415.
Upon failure of the normal power supply, the
emergency generator is placed on the line by the
__________.
A. main bus feeder
B. automatic bus transfer device
C.line connection feeder
D.power failure alarm bus
Ans. B
138
416.
In a simple mechanical governor, the ____.
A. centrifugal force rotates the ball-head
B. flyweight centrifugal force is balanced by spring
force
C.flyweight centrifugal force is balanced by
hydraulic pressure
D.speeder spring alone actuates the fuel control
rod
Ans. B
417.
The type of control circuit that will NOT
permit automatic restarting after power is restored,
following a power failure is called ______.
A. low voltage protection
B. low voltage release
C.overload lockout
D.reduce voltage restart
Ans. A
418.
Which of the listed feature does the Coast
Guard Regulations require of a motor controller
which must be manually restarted following a
power failure?
A. Overload protection
B. Low voltage release
C.Low voltage protection
D.Reverse current protection
Ans. C
139
419.
The type of feature afforded auxiliaries vital
to the operation of propelling equipment, where
automatic restart after a voltage failure would not
create a hazard, is termed _______.
A. low voltage protection
B. high amperage protection
C.low voltage release
D.high amperage release
Ans. C
420.
Which of the listed items will stop a motor
due to a reduction in voltage and restart it when the
voltage is restored to normal _______.
A. low voltage protection circuit
B. non-renewable link fuse
C.renewable link fuse
D.low voltage release circuit
Ans. D
421.
In half-wave rectifier can use with or without
_______.
A. diode
B. capacitor
C.transformer
D.resistor
Ans. C
422.
What is NOT part of maintenance work on
brushes and commutator?
140
A. Apply coat of mineral oil/solvent
B. Replace worn brushes
Ans. A
423.
Which of the damages listed can occur to the
components of a winch master control switch, if the
cover gasket becomes deteriorated?
A. Overheating of the winch motor
B. Contamination of lube oil
C. Sparking at the winch motor brushes
D. Rapid corrosion of switch components
Ans. D
The full torque electric brake on an electric cargo
426. winch functions to ___.
a. act as a backup brake in case the
mechanical brake should fail
b. automatically hold the load as seen as
current to the machine is shut off
c. automatically reduce lowering speed
d. automatically reduce hoisting speed
Ans. B
427. Moisture damage due to consideration inside the
141
cargo winch master switches can be reduced
by _____________.
a. installing light bulb in the pedestal stand
b. sealing the switchbox
c. venting the switchbox regularly
d. using strip heaters inside the switch box
Ans. D
In the event of a power failure during cargo
428. loading operations, the movement of an electric
powered cargo will be stopped by ______.
a. manual override switch
b. spring set brake
c. hand-operated brake
d. weight of the boom load
Ans. B
The greatest enemy of an idle electrical
429. equipment such as a pump
room fan motor is the _____________.
a. loss of magnetism
b. moisture in the insulation
c. insulation varnish flaking
d. dirt accumulation on the windings
Ans. B
Which of the following represents the best method
430. of cleaning dust from electrical circuits in order
142
to limit damage to electronic components?
a. wipe off with soft cotton rag
b. use high velocity compressed air
c. use vacuum cleaner
d. use chemical solvent
Ans. C
In an induction motor, rotor currents are circulated
431. in the rotor by ____.
a. slip ring and brushes
b. armature and brushes
c. inductive reaction of rotating stator field
d. external variable resistor
Ans. C
A circuit breaker and a fuse have basic similarity
432. in that they both ____.
a. can be reset to energize the circuit
b. should open the circuit when overload
develops
c. will burn out when overload develops
d. all of these choices
Ans. B
Electrical leads and insulation on a motor should
433. be painted with ___.
143
a. heat resisting acrylic
b. heat resistant aluminum
c. insulating varnish
d. insulating white lead
Ans. C
A degree of control over speed of slip ring
434. induction motor can be obtained by _______.
a. adjusting governor linkage
b. changing the number of coils on the motor
c. inserting assistance to the stator
d. inserting resistance to the rotor
Ans. D
A circuit breaker differs from a fuse because a
435. circuit breaker can ___.
a. melt and be replaced
b. enclosed tube has insulating material
c. gives no visual condition
d. trips to break the circuit and my be reset
Ans. D
The main purpose of an auxiliary windings as a
436. split-phase, single-phase motor is to____.
a. limit the starting voltage
b. increase starting current
c. start the motor
d. keep the motor running
Ans. C
The state of charge of a lead acid storage battery
437. is best indicated by _____________.
144
a. testing individual cell voltages
b. ampere hour capacity
c. specific gravity of electrolyte
d. total cell voltage
Ans. C
A low voltage source is being used for testing
438. armature coils. A short circuit will be indicated
by a _____________.
a. high voltage reading
b. zero or low voltage reading
c. fluctuating voltmeter reading
d. steady voltmeter reading
Ans. B
Which of the listed procedures should be carried
439. out to prevent moisture damage to idled
electrical apparatus?
a. inert the space
b. strap silica gel
c. place heat lamps
d. cover the equipment with canvass
Ans. C
145
Electric heaters are used in motor controllers to
440. _____________.
a. prevent movable contacts from freezing
b. keep components warm
c. prevent condensation of moisture
d. maintain good resistance of circuit
Ans. C
A fuse that blows often should be replaced only
441. with fuse of _______.
a. recommended current and rating
b. higher current and rating
c. lower current and rating
d. none of these choices
Ans. A
Which of the listed precautions should be
442. observed before spraying liquid solvent on the
insulation of an electric motor?
a. slow the motor down to low speed
b. disconnect the motor from the power source
c. secure all ventilation in the area
d. pre-heat the insulation
Ans. B
146
On a tanker vessel with electrically driven
443. capstan, the motor should be megged
periodically to test _____________.
a. insulation resistance
b. eddy currents
c. capacitance
d. armature reactance
Ans. A
A reverse power current relay prevents AC
444. generator motorization automatically by ___.
a. transferring the load
b. speed up the prime mover
c. secure the exciter generator
d. tripping the circuit breaker
Ans. D
Which of the following devices will prevent an AC
445. generator from becoming motorized?
a. overcurrent relay
b. relay trip
c. governor control switch
d. reverse current relay
OR
a. Overspeed trip
b. back pressure trip
c. Governor control
d. Reverse power relay
Ans. D
446. A grounded switch or cable will be indicated by a
megohmeter of _____________.
147
a. infinity
b. zero
c. unsteady reading in high range
d. unsteady reading in low range
Ans. B
Batteries used for diesel engine starting should
447. _____________.
a. be located in a locker on the weather deck
b. be located as close as possible to the
engine
c. have capacity to start the engine up to 50
times
d. none of these choices
Ans. B
Before testing insulation with a megohmeter, the
448. windings of large machines should be grounded
for 15 minutes because ___________.
a. static charge in the machine
may give false reading
b. insulation may get damaged
c. insulation may be wet
d. machine may run automatically
Ans. A
148
Battery charging rooms should be well-ventilated
449. because the charging process _____.
a. produces highly poisonous hydrogen
b. produces highly combustible oxygen
c. liberates explosive gases
d. liberates corrosive gases
Ans. C
When a megger is used to test insulation, the
450. gradual rise of the pointer reading as a result
of continued cranking, is caused by
___________.
a. good resistance
b. leakage in the winding
c. inductive resistance in windings
d. dielectric-absorption effect of the insulation
Ans. D
Most 3-phase induction motors for driving engine
451. room auxiliaries are started by ______.
a. resistor starters
b. across-the-line starters
c. impedance starters
d. reactor starters
Ans. B
First aid treatment for battery acid or alkali burns,
452. especially in the eyes, includes ______.
149
a. flushing with large amounts of fresh water
b. wiping the affected area with clean dry cloth
c. using talcum powder to counter itching
d. all of these choices
Ans. A
453. A hydrometer is used to measure __________.
a. specific gravity of battery electrolyte
b. water pressure on deck line
c. amount of distilled water evaporator
produced
d. power developed by sea water service
pump
Ans. A
Discharge switches are often located on hand454. driven meggers. The purpose of these switches
is to discharge capacitive charges
stored in the _______________.
a. megger hand generator
b. movement coils
c. tested equipment while conducting test
d. tested equipment after conducting test
Ans. D
150
455. A megohmmeter can be used to test for ______.
a. an open field
b. synchronous speed
c. frequency
d. high voltage presence
Ans. A
You are attempting to parallel two AC generator
456. and the synchroscope pointer is revolving
slowly in the fast direction. You should ________.
a. use the governor switch to adjust incoming
voltage so it is equal to the voltage
b. use the governor switch to increase the
speed of the prime mover
c. close the circuit breaker when the
synchroscope pointer approaches
“0” position
d. close the circuit breaker when the
synchroscope pointer approaches
“180” position
Ans. C
A fuse will blow for all the listed reasons except
457. _____________.
a. excessive vibration
b. extremely hot surroundings
c. loose fuse clips
d. low contact resistance within the fuse
Ans. D
458. Moisture absorbed in the windings or condensed
151
on the surface of electrical machinery
insulation _____________.
a. is good for the machinery as additional
insulation
b. lowers insulation value and may create
grounds
c. enhance insulation value of the machine
d. reduce the amount of current to be fed to the
machine
Ans. B
In which of the situation listed will a
459. megohmmeter give the most
accurate reading ?
a. while the machine is in operation
b. while the machine is about to stop
operation
c. immediately after the machine has stopped
d. 15 minutes after the machine has been
isolated and grounded
Ans. D
When using a multimeter for resistance
460. measurements, it should be calibrated by clipping
the loose ends of the leads together and ____.
a. setting the instrument pointer at zero ohms
b. adjusting the line voltage to calibrate the
instrument
c. plugging each end of one test lead into the
plus and minus terminals
d. using special purpose resistance measuring
152
instruments
Ans. A
Which of the following insulation will deteriorate
461. first as a result of heat generated in the conductor
it surrounds ?
a. rubber
b. varnished cloth
c. silicon
d. asbestos
Ans. A
462. A multimeter can be used to measure _______.
a. resistance
b. voltage
c. current
d. all of these choices
Ans. D
Which of the following problems will most likely
463. occur if the starting winding of a split-phase
induction motor failed to cut-out once the
motor was in continuous operation?
a. the motor will overspeed
b. the motor will run at a reduced speed
c. the motor will stop
d. the winding will burn out
153
Ans. D
When insulation failure produces a low resistance
464. current path between two conductors, the
resulting condition is known as _____________.
a. an open circuit
b. a short circuit
c. a ground
d. a surge
Ans. B
When disassembling motor for maintenance or
465. overhaul _________.
a. punch mark frame and end bells for proper
assembly
b. wrap bearings in lint free cloth if they are to
be reversed
c. tag and store small parts in a box
d. all of these choices
Ans. D
466. Fuses are usually rated in _____________.
a. watts
b. amps only
c. volts only
d. amps and volts
Ans. D
467. When used for taking resistance measurements,
154
voltage-ohmmeter is normally paired by ______.
a. a hand cranked generator
b. internal storage batteries
c. the current in the circuit being tested
d. a step-down transformer
Ans. B
When an AC or DC motor fails to start, the FIRST
468. step in troubleshooting should be to check
the _____________.
a. motor windings for obvious opens
b. motor controller leads for continuity
c. fuse or circuit breaker
d. motor controller leads to ground
Ans. C
A current-carrying conductor making electrical
469. contact with a wiring conduit will be indicated
by a _____________.
a. high switchboard wattmeter reading
b. totally dark switchboard ground detecting
light
c. low switchboard wattmeter reading
d. all of these choices
155
Ans. B
To remove an alternator operating in parallel with
470. mother unit from the main electrical bus,
you must FIRST _____________.
a. adjust the power factor on both units
b. set the desired voltage on the outgoing
alternator
c. open the circuit breaker on the outgoing
alternator
d. remove the load from the outgoing
alternator
Ans. D
When testing for blown fuses in a three-phase
471. supply circuit to a motor, you should first
______.
a. apply the megger across the tops of the line
fuses
b. apply the megger across the bottom of the
line fuses
c. apply the voltage faster across the bottom of
the line fuses
d. de-energize the circuit and then use a
continuity tester
Ans. D
In a three-phase electrical system, three ground
472. detecting lamps are provided. If all three lamps
REMAIN at half brilliance when the ground
detecting switch is operated ______.
a. there is a slight ground on all three phases
b. the switch must be replaced
c. there are no grounds present
d. the light bulbs are of improper voltage
156
Ans. C
Electrical failures in motors are caused by the
473. breakdown of insulation, which maybe caused
by ______.
a. penetration of moisture
b. accumulation of dirt
c. overheating
d. all of these choices
Ans. D
In order to safely carry out repairs to a generator
474. circuit breaker, it must be isolated from
the bus. This is accomplished by opening the
________.
a. reverse power relay
b. bus disconnect link
c. generator bus fuse connection
d. power directional relay
Ans. B
If the voltage supplied to the lightning circuit is
475. 110 volts. How much current is used by a
100 watt light bulb ?
a. 0.08 amps
b. 0.91 amps
c. 1.10 amps
d. 90.9 amps
Ans. B
157
According to USCG regulation (CFR 46) which of
476. the ff systems must be arranged so as to be
energized by emergency power supply in case of
power failure?
a. at least one light is steering gear room
b. each power operated watertight door
system
c. each changing panel for temporary
emergency batteries
d. all of these choices
Ans. D
Diesel generator # 1 & 2 are operating in parallel
477. at near full load capacity. Diesel generator # 1
suddenly trips out mechanically due to low lube oil
pressure. The reverse power relay functions
properly and trips generator # 1 off the board.
Which of the following should
you do FIRST?
a. start the standby generator
b. ascertain cause of low lube oil pressure
c. strip the board of non-vital loads
d. secure alarm, reset all tripped relays and
restart generator # 1
Ans. C
The source of emergency lightning and power at
478. loss of normal-ship’s power on a cargo vessel
should be obtained from the _____________.
a. emergency switchboard
b. main switchboard
c. emergency batteries
d. emergency power from main switchboard
158
Ans. A
International regulations states that continuous
479. trickle charge supplied from the ship’s required
service power system, is for batteries supplying
power to the __________.
a. emergency diesel starting system
b. emergency power system for radar
c. emergency power system for steering gear
d. emergency power system for lifeboat radios
Ans. A
According to USCG Regulation 46CFR, the
480. talking and calling circuits of a sound powered
telephone system must be __________.
a. intrinsically safe
b. independent of each other
c. independently grounded
d. connect to a common ground
Ans. B
Which of the listed safety features should be
481. provided in a small room or locker
where batteries are stored?
a. install a CO2 system
b. install an exhaust system fan
c. an exhaust duct to be made 3 feet above
the deck
d. exhaust duct is to be provided from the top of
159
the locker to open air
Ans. D
You should not allow salt water to enter a lead
482. acid battery or come in contact with sulfuric
acid because _____________.
a. resulting gas is extremely flammable
b. the resulting gas is a respiratory irritant that
can be fatal
c. the primary constituent, sodium, reacts
lethally with lead peroxide
d. continuing salt water with lead acid creates a
harmful gas
Ans. B
Which of the ff should be done when a 10 amp
483. blown fuse is replaced ?
a. short out the fuse
b. replace blown fuse with less than 10 amp
rating
c. replace blown fuse with exactly 10 amp
rating
d. none of these choices
Ans. C
International Regulations requires that an
484. indicating light at the
propulsion control station will activate if
overloading or overheating
occurs in a ____________.
a. forced draft fan
b. steering gear motor
160
c. fuel pump motor
d. condensate pump motor
Ans. B
International regulations requires that a remote
485. stop/start button for engine room bilge
pump shall be located at _____________.
a. main deck / upper deck
b. emergency generator room
c. engine control room
d. cargo control room
Ans. A
International regulations requires a continuous
486. trickle charge is to be applied from the ship’s
service power system for batteries
supplying power to the ___________.
a. emergency power for bridge and engine
control rooms
b. portable radios fro the lifeboat
c. emergency power and lightings
d. all of the above
Ans. C
A multimeter may be damaged by taking a
487. _____________.
a. voltage reading while in the resistance
mode
b. current reading while in voltmeter mode
c. resistance reading while in the ammeter
mode
161
d. resistance reading while in the voltmeter
mode
Ans. A
488. When replacing fuses, always make sure _____.
a. to stand on a rubber mat and use rubber
gloves
b. to use insulated pliers or screwdrivers
c. the fuse clips are straight, tight and holding
the new fuses well
d. to increase the fuse rating by 1-% to guard
against “nuisance” blowing
Ans. C
If all the grounds lamps burn with equal brilliance,
489. whether the test button is depressed and
released, which of the listed conditions is
indicated?
a. no ground exist
b. all three phases are grounded
c. the test switch is faulty
d. the current transformers are shorted out
Ans. A
The ground indicating light on the main
490. switchboard is indicating a ground.
The last procedure for locating the grounded
circuit is to ____________.
a. trace the circuit’s paths while looking for
burned spots
b. open the circuit breakers on the distribution
162
panel one by one until the lights no longer
indicate a ground
c. check circuits for continuity
d. none of these choices
Ans. B
491. An ohmmeter can be used to test for ________.
a. an open field coil
b. a shorted field pole
c. reverse polarity
d. low voltage supply
Ans. A
Electrical machinery insulation will breakdown
492. more rapidly due to ________.
a. low loading of motor and generators
b. frequent megger testing
c. high temperature and vibration
d. high operating frequencies
Ans. C
Low horsepower, poly-phase conduction motors
493. can be started with full voltage by means
of _____________.
a. compensator starters
b. auto transformer starters
c. across the line starters
d. primary resistor starters
163
Ans. C
Which of the following conditions will occur if the
494. solenoid coil burns out on a cargo winch
with an electric brake ?
a. the brake will be set by spring force
b. the motor will overspeed and burn out
c. the load suspended from the cargo boom
will fall
d. none of these choices
Ans. A
External shunts are sometimes used with
495. ammeters to _____________.
a. increase meter sensitivity
b. prevent shunts with larger resistance to be
utilized
c. prevent damage to the meter movement from
heat generated by the shunt
d. enable the construction of a compact meter
with a virtually unlimited range
Ans. C
Which of the following statements is correct in the
496. maintenance of contacts in relays ?
a. they should dressed with wire wheel
b. they should be dressed w/ fine cut file if
surface is uneven
c. if burns are noticed, at should be removed w/
164
sandpaper
d. should be held together with every paper
driven between contacts
Ans. B
A signal derived from a controlled function and
497. returned to the initiating point
is called a/an _____________.
a. monitoring signal
b. inverse signal
c. reverse signal
d. feedback signal
Ans. D
A device which prints out a permanent record of
498. the plant operating conditions is known
as the _____________.
a. analog logger
b. bell book
c. alarm logger
d. data logger
Ans. D
The speed of squirrel cage induction motor is
499. determined by the _______.
a. diameter of the stator
b. no. of stator poles
c. rotor winding resistance
d. stator winding resistance
165
Ans. B
Under which of the listed conditions can the
500. engine room retake the throttle control
from the bridge ?
a. anytime it deemed necessary
b. only w/ master’s permission
c. after 10 min. delay to the command
d. only when the throttle is at stop
Ans. A
A generator has been exposed to water and is
501. being checked for its safe operation. Therefore
it is necessary to ________.
a. check for shorted coils
b. take moisture reading
c. test insulation reading
d. ground the commutator and run it for half an
hour
Ans. C
A squirrel-cage motor is designed to have
502. _____________.
a. low starting voltage
b. low starting current
c. high starting voltage
d. low starting resistance
166
Ans. B
In a DC series circuit, all the conductors have the
503. same _____________.
a. power consumption
b. voltage drop across
c. current passing thru them
d. resistance passing thru them
Ans. C
Which of the AWG wire sizes listed below would
504. have the smallest diameter ?
a. 000
b. 0
c. 12
d. 250
Ans. C
When using a megger to test insulation, good
505. insulation will be indicated by ______.
a. slight kick of the needle downscale
b. downward dip followed by gradual climb to
the true resistance value
c. initial dip of pointer
d. gradual rise in the pointer
Ans. B
A reverse-current relay will prevent DC generator
506. motorization by _______.
a. automatically redirecting the load
b. automatically speeding up the prime mover
c. tripping the panel board main switch
d. tripping the generator circuit breaker
167
Ans. D
If many turns of an alternating current coil
507. contractor become short circuited, the coil ___.
a. temperature will drop
b. will probably burn out completely
c. will continue to operate
d. will operate on reduced current
Ans. B
How is a wattmeter electrically connected in a
508. circuit ?
a. in series
b. in parallel
c. in series-parallel
d. inductively
Ans. C
Which of the listed conditions would indicate the
509. need for cleaning electrical insulation ?
a. low ambient temperature
b. low operating temperature
c. high dielectric strength
d. low megger readings
Ans. D
Multiple grounds have developed and were
510. initially indicated by the ground detecting
system as one ground. The first step in locating
ground is to _____________.
168
a. examine the main bus bars for signs of
overheating
b. eliminate the individual circuits one by one
until the ground detecting
system no longer indicates any grounds
c. change over generators
d. check each circuit with a megohmeter
Ans. B
To protect the rotor of a motor disassembled for
511. maintenance or overhaul, it should
be _____________.
a. suspended by wire slings in one corner of
the shop
b. wrapped it with heavy papers or lint free
cloth
c. support by flat wood blocks on the
workbench
d. return to the frame as soon as the bearing is
removed
Ans. B
Which of the following material is a good
512. insulator ?
a. glass
b. steel
c. aluminum
d. copper
Ans. A
Which of the conditions listed below will indicate
513. the need to clean the insulation on the
windings of an electric motor?
a. higher than normal operating temperature
169
b. excessive vibration at normal speed
c. sparking at the brushes
d. high megger readings
Ans. A
If the energy input is significantly reduced to the
514. prime mover of one shipboard alternator
operating in parallel with others, that alternator will
___.
a. continue to operate at no load
b. lose its load and overspeed
c. begin to motorize and then trip out
d. slow down and operate at reduced load
Ans. C
The failure of ball bearings used in electric motors
515. can result from ________.
a. failure to clean the bearing before repacking
b. failure to maintain proper alignment
c. excessive grease in bearing thus eliminating
room for expansion
d. all of these choices
Ans. D
Which of the listed condition will occur if dirt and
516. grease are allowed to accumulate between
the commutator segments of a motor?
a. partial short circuit
b. a dead short circuit
c. misalignment of the motor shaft
d. overspeeding of the motor
Ans. A
170
A damp armature windings in an AC motor may
517. lead to _______________.
a. reduced voltage
b. reduced current
c. Increased resistance
d. overheating
Ans. D
A single-phase induction motor starts, reaches
518. 75% rated speed, slows down and accelerates
again. The problem is most likely in the _____.
a. starting winding
b. running winding
c. starting capacitor
d. running centrifugal switch
Ans. B
On large generators, space heaters are used to
519. _______________.
a. keep the machine at ambient temperature of
the machinery space
b. maintain motor parts above dew point to
prevent condensation
c. prevent condensation on the bearings
d. prevent stack up of rotating parts
Ans. B
If a brush on a DC generator is only partially
520. seated, which of the following problems may
occur?
a. high current density developing at the contact
surface
b. continual overheating at the brush line
171
c. the brush will spark during the operation of the
generator
d. all of these choices
Ans. D
Most conducting materials such as copper,
521. aluminum, iron, nickel
and tungsten ______.
a. increase in resistance with increased
temperature
b. increase in resistance with decreased
temperature
c. decrease in resistance with increased
temperature
d. increase in conductance with increased
temperature
Ans. A
Electric motor ball bearings designed to be filled
522. with grease should have the relief plug
temporarily renewed while grease is
being added. This plug should remain out until the
machinery has been operated and
warmed up to ensure that __________.
172
a. a path of expansion is provided for the
grease
b. all air pockets are vented from the grease
c. dirt and grit are flushed from the bearing
house
d. the grease is properly distributed within the
bearing
Ans. A
A large generator is provide with a space heater
523. to ________________.
a. keep the machine at ambient temperature of
the machinery space
b. maintain rotor and stator winding temperature
above dew point
c. prevent condensation in the lube oil
d. prevent electrolysis due to condensation in the
bearings
Ans. B
If air gap readings from an electrical generating
524. machine have changed significantly from
the last reading, you should check __________.
a. the bearings
b. insulation readings and machine
cleanliness
173
c. prime movers thrust bearing
d. the field coil bolts for proper tightness
Ans. A
Routine AC motor maintenance should include
525. periodic ____________.
a. temperature readings at normal loads to
detect abnormal temperature rise
b. inspection of motor internals for loose rotor
bars
c. verifying the RPM is within normal range
d. all of these choices
Ans. A
When removing ball or roller bearings from the
526. shaft of a motor, you should use a ___.
a. rawhide hammer
b. brass mallet
c. wheel puller
d. soft iron pry bar
Ans. C
A circuit that has one of two wires in contact with
527. the hull of a ship is called a_______.
a. grounded circuit
b. short circuit
c. series circuit
d. closed circuit
174
Ans. A
Encrusted dirt accumulated inside a motor should
528. be removed with a _________.
a. fiber scrapper
b. painted welding rod
c. hammer and chisel
d. paint scraper
Ans. A
Silicone diodes designed for a specific reverse
529. breakdown voltage, become useful as an
electronic power supply voltage regulator is called
________________.
a. tunnel diodes
b. hot-carrier diodes
c. compensating diodes
d. zener diodes
Ans. D
Which of the listed devices may be used as a
530. digital device?
a. variable resistor
b. diode
c. strain gauge
d. thermistor
Ans. B
Which of the listed condition is an advantage of a
531. PN diode over a vacuum diode?
a. longer life
b. no warm up time
c. less delicate
175
d. all of these choices
Ans. D
532. Heat sinks are frequently used with _______.
a. power transistors
b. vacuum tubes
c. tunnel rectifier diodes
d. all of these choices
Ans. A
533. A semiconductor is a material with a ________.
a. conductivity higher than a normal conductor
b. conductivity higher than a normal insulator
c. high conductivity at low temperature
d. low conductivity at high temperature
Ans. B
Which of the listed conditions describes the effect
534. on intrinsic semiconductor operation as a
result of a temperature increase?
a. capacitive reactance will decrease
b. conductivity will increase
c. inductive reactance will decrease
d. resistivity will increase
Ans. B
Brushless generators are designed to operate w/
535. out the use of _____________.
a. brushes
b. slip rings
176
c. commutator
d. all of these choices
Ans. D
On a diesel electric plant, raising the generators
536. field excitation will cause the DC propulsion
motor to _____________.
a. increase in speed
b. decrease in speed
c. affect the generator speed only
d. affect the main motor speed
Ans. A
Electric propulsion coupling excitation is reduced
537. at slow speeds to_____________.
a. increase speed control
b. increase shaft torque
c. prevent coupling from overheating
d. prevent coupling from slippage
Ans. C
When choosing a battery for a particular
538. application, major consideration
should be given to the battery’s
_____________.
177
a. ampere hour capacity
b. terminal polarity
c. stability under changes
d. ambient temperature rise
Ans. A
An electrical device w/c employs a stationary
539. armature and a rotating
electromagnetic field is used aboard ship as a
___________.
a. magnetic amplifier
b. ship service alternator
c. three-wire generator
d. saturable reactor
Ans. B
A lead-acid battery is considered fully charged
540. _____________.
a. when the electrolyte is gassing
b. ammeter indicates positive reading
c. terminal voltage reaches constant value
d. specific gravity no longer increases 1 to 4
hours
Ans. D
Electrical circuits are protected against
541. overheating by means of a/an _______.
a. circuit breaker
b. amplifier
c. diode
178
d. capacitor
Ans. A
Which of the following electrical properties will be
542. the same with respect to each component
in series circuit?
a. voltage
b. current
c. resistance
d. inductance
Ans. B
Which of the following components are used to
543. convert AC to DC?
a. armature and equalizer
b. commutator and brushes
c. rotor and interpoles
d. field excitation
Ans. B
Line loses in a distribution circuit are kept to a
544. minimum by _____________.
a. adding rubber insulation in the circuit
b. using high current and low voltage
c. increase boosters in the line
d. using higher voltage and low current
Ans. D
To minimize magnetic field excitation between
545. electrical conductors in physical proximity,
it is best to keep them _____________.
a. parallel and as close as possible to each
other
179
b. at right angles with each other
c. parallel and far away from one another
d. at right angles and as far away as practicable
for one another
Ans. D
As insulation resistance reading is taken at 20
546. degrees Celsius and found to be 10 megohms.
What would expect the resistance reading
a. 2.5 ohms
b. 10 ohms
c. 15 ohms
d. 20 ohms
Given: Insulation Resistance Temp. = 20o
Standard Insulation Temp. = 40oC
Resistance RDG?
Formula R40 = KT x RT
Where: R40 = Corrected IR
KT = Correction Factor
RT = Insulation Resistance
RDG for diff. temp.
Ans. A
The amount of current flow required for the
547. cathodic protection of a vessel is dependent
upon the _____________.
a. amount of bare steel surface
b. speed of the ship through water
c. temperature of the water
d. all of these choices
Ans. D
When paralleling two AC generator, which of the
548. following actions should be the final step?
a. adjusting the governor
b. balancing the load
c. closing the circuit breakers
d. closing the equalizing switch
180
Ans. B
Which type of AC single-phase motor will also
549. operate on DC ?
a. split-phase
b. series-wound
c. shaded pole
d. repulsion-start
Ans. B
The standard procedure for maintaining the
550. charge in a battery is to trickle charge _______.
a. continuously
b. at least once a week
c. whenever the charge falls below 75%
d. whenever the specific gravity falls below
1.2
Ans. A
A lead acid battery may become hotter than
551. normal during a charge if the _______.
a. battery has shorted cell
b. charging voltage is low
c. specific gravity is too high
d. battery room door is secured
Ans. A
Before touching a small capacitor connected to
552. de-energize circuit, or even the one that is
completely disconnected, one should
_______________.
a. tap it with screwdriver
b. use a de-energise tag
181
c. use a puller
d. short circuit the terminal
Ans. D
Kilowatt load is divided between two AC
553. generators operating in parallel by _______.
a. adjusting the governor control
b. varging the excitation voltage
c. increase prime mover speed
d. decrease prime mover speed
Ans. A
In a simple series circuit, the entire source voltage
554. will drop across _____________.
a. the resistor next to the negative terminal
b. a short circuit
c. an open circuit
d. resistor next to the terminal
Ans. C
Excessive heat in an operating motor controller
555. can result from _____________.
a. a closed starter contact
b. loose connection
c. missing arc chute
d. low motor starting torque
182
Ans. B
556. An ammeter should be used to measure _____.
a. the voltage between two points in a
circuit
b. circuit continuity
c. current flow in a circuit
d. total or partial circuit resistance
Ans. C
What is the approximate voltage per cell produced
557. by the nickel-iron battery?
a. 0.25 volts
b. 1.35 volts
c. 1.5 volts
d. 6.0 volts
Ans. B
Which of the methods listed below is used to start
558. an AC generator turning?
a. residual magnetism remaining in the field
poles
b. residual magnetism remaining in the field
coils
183
c. residual magnetism remaining in the
armature
d. none of these choices
Ans. D
A handheld digital tachometer could give a bad
559. reading if _____________.
a. aimed directly at the shaft
b. partially aimed at the fluorescent light
bulb
c. the tape is too shiny
d. positioned too close to the shaft
Ans. B
Under normal condition storage batteries used for
560. starting emergency diesel generator
are maintained in a charged state by which of the
following methods?
a. trickle charging
b. fast charging
c. equalizing charge
d. full charging
Ans. A
The number of cycles per second occurring in an
561. AC voltage is known as the ____.
a. phase angle
b. frequency
c. wave form
184
d. half mode
Ans. B
When the electrolyte level of lead-acid storage
562. battery has decreased due to normal
evaporation, the level should be re-established by
adding _______?
a. distilled water only
b. sulfuric acid only
c. a weak solution of distilled water and
sulfuric acid
d. a strong solution of distilled water and
sulfuric acid
Ans. A
Which of the listed classes of electrical insulation
563. are suited for the highest operating temperature?
a. class O-90
b. class A-105
c. class B-130
d. class H-180
Ans. D
The armature cores of DC motors are constructed
564. with laminators to _________.
a. eliminate hysteresis
b. minimize brush sparking
c. reduce eddy current loses
d. compensate for armature reaction
185
Ans. C
When paralleling two AC alternators using
565. synchronizing lamp only, both lamps
will go dark when the alternators are
__________.
a. running at the same speed
b. grounded
c. of same polarity
d. in phase
Ans. D
A lead-acid battery cell sustaining short circuit
566. _______________.
a. will have unusually high voltage
b. will be indicated by lime accumulation on the
terminal posts
c. have excessively high temperature while
being charged
d. cannot complete full charging
Ans. C
Which of the instrument listed below is used for
567. checking insulation?
a. magnetometer
b. megohmmeter
c. dynamometer
186
d. ammeter
Ans. B
Equalization of the power factors of two
568. alternators operating in parallel
is accomplished _____________.
a. manually, by adjusting the governor
control
b. automatically, by automatic voltage
regulators
c. manually, adjusting the output of current
transformer
d. automatically, by the designed action of the
governors
Ans. B
The field strength of a ship’s service DC generator
569. is adjusted by varying the ____.
a. speed of the generator
b. no. of field poles on the line
c. power factor of the field
d. resistance in the field
Ans. D
To parallel two generators, you should start the
570. prime mover _____________.
a. close the circuit breaker, adjust the voltage
then balance the loads
187
b. close the circuit breaker, adjust the bus
voltage then balance the loads
c. close the circuit breaker and the equalizer
switch then balance the loads
d. adjust the voltage, close the circuit breaker
then balance the loads
Ans. D
A lead acid battery can deliver 20 amperes
571. continuously for 10 hours with
an ampere-hour rating of _____________.
a. 20
b. 40
c. 200
d. 400
Ans. C
Which of the following statements, concerning the
572. general maintenance of a brushless
generator is correct?
a. paint should be applied to insulating surfaces
on an annual basis
b. alcohol should be used to remove dust and
grime from the windings
c. high pressure air should be used to blow out
carbon dust
d. accessible generator parts should be wiped
with a clean dry rag on a periodic basis
Ans. D
573. The inductance of a coil is measured in _____.
a. ohms
b. volts
c. henries
188
d. amperes
Ans. C
574. The resistance of a conductor varies ______.
a. directly as its length and inversely as its
cross sectional area
b. inversely as its length and directly as its
cross sectional area
c. directly as its length and directly its cross
sectional area
d. inversely as its length and inversely as its
cross sectional area
Ans. A
The Wheatstone bridge is a precision measuring
575. instrument utilizing the principle of
changes in _____________.
a. inductance
b. capacitance
c. resistance
d. amperage
Ans. C
Which of the following should be the FIRST step
576. in removing a generator from parallel operation?
a. trip the generator off the switchboard
b. turn off the electrical equipment
c. remove the load from the off-going
generator
189
d. increase the cycle of the generator staying
on the line
Ans. C
To limit the current flow through a DC voltmeter to
577. as low as possible, the moving cool circuit
is provided with a/an __________.
a. high series resistance
b. high parallel resistance
c. average voltage
d. peak voltage only
Ans. A
Most AC voltmeters are calibrated to indicate
578. _____________.
a. peak-to-peak voltage
b. root mean square voltage
c. average voltage
d. peak voltage only
Ans. B
Which of the ff conditions indicates a short579. circuited capacitor when ducking
condition with an ohmmeter?
a. the capacitor shows changing but the final
resistance reading is appreciably less
than normal
b. the reading is practically zero and remains
190
there
c. the capacitor shows no changing action, but
indicates a very high resistance
d. the pointer moves quickly to the low
resistance side of the scale, then slowly
recedes towards infinity
Ans. B
Hand portable phase sequence indicators are
580. useful when _____________.
a. preparing to parallel alternator
b. connecting lighting branch circuits
c. trouble-shooting DC motors
d. correcting shore power lines to the ship
Ans. D
The capacity of storage battery is measured in
581. _____________.
a. amp-hour capacity
b. volts
c. farads
d. amps
Ans. A
You are paralleling two alternators. The
582. synchronizing lamps grow dim and are totally
darkened as the synchroscope pointer
approaches the "0" position.
This indicates that the _____________.
a. alternator voltage are 180 degrees apart
191
b. circuit breaker can be closed
c. incoming alternator is running too slowly
d. synchroscope is defective or broken
Ans. B
When mixing electrolyte for a lead-acid battery
583. _____________.
a. stirring should always be avoided
b. a lead container should always be used
c. always pour the water into the acid
d. always pour the acid into the water
Ans. D
Which of the listed forms of water should be
584. added to a lead-acid battery?
a. saltwater
b. brackish water
c. distilled water
d. light water
Ans. C
Which of the problems listed below will occur with
585. a lead-acid battery is allowed to
remain in a discharged position for a long period
of time?
a. the battery may not be able to accept a full
charge
192
b. the electrolyte will turn sour
c. the corticosteroid sulfuric acid will attack
the plates
d. the separators will harden
Ans. A
When you check the specific gravity of the battery
586. electrolyte with a hydrometer, it should be
kept in mind that _____________.
a. the battery is fully charged when the indicator
floats low in the electrolyte
b. any water that has been previously added to
the cells will dilute the solution and give
false reading
c. a hydrometer reading is inaccurate if taken
immediately after water is added
to the cell
d. temperature has an effect on hydrometer
readings
Ans. C
A reverse current relay will prevent AC generator
587. motorization by _____________.
a. automatically redirecting the load
b. automatically speeding up the prime
mover
c. tripping the panel board main switch
193
d. tripping the generator circuit breaker
Ans. D
One of the generator or motor bearings is
588. generally insulated from the end housing in
order to prevent _____________.
a. rapid brush wear
b. current leakage from shaft
c. excessive field winding heat
d. circulation of shaft currents induced in the
machine frame
Ans. D
An increase in the mount of current flow through
589. the armature of a shunt motor is
the final result of a/an _____________.
a. increase in the load on the motor
b. decrease in the load on the motor
c. increase in counter EMF
d. decrease in armature torque
Ans. A
A motor enclosure which protects against falling
590. liquids is classified as _________.
a. waterproof
b. drop proof
c. spray tight
194
d. moisture free
Ans. B
Insufficient brush pressure on a DC motor may
591. cause _____________.
a. generator overload
b. excess residual magnetism
c. water vapor absorption
d. sparking of the brushes
Ans. D
The type of motor control circuit that fails to pick
592. up when the coil voltage is
applied to the contractor coil, the cause may be
_____________.
a. low voltage protection
b. low voltage release
c. overload lock-out
d. reduced voltage starter
Ans. A
If magnetic controller contactor fails to pick up
593. when the coil voltage is applied
to the contactor coil, the cause may be
_________.
a. overload
b. misalignment of contacts
195
c. low spring pressure
d. an open contactor coil
Ans. D
The use of four diodes, in a full-wave bridge
594. rectifier circuit, will _____________.
a. provide unidirectional current on load
b. allow high leakage current on load
c. convert DC to AC
d. all of these choices
Ans. A
Motor controllers are seldom troubled with
595. grounds because _____________.
a. the auxiliary contact have high resistance
connection
b. the contractors and relays are mounted in a
non-conducting panel
c. the resistor banks are ground-proof
d. separate switches are available
Ans. B
A constant out voltage from an AC generator is
596. maintained by the _____________.
a. prime mover
b. voltage regulator
c. exciter generator
196
d. reverse power relay
Ans. B
597. Power transformers are rated in _______.
a. kilowatts
b. ampere turns
c. kilowatt-volts
d. kilovolt-amperes
Ans. D
An insulation test is performed on an electrical
598. equipment. Besides resistance
reading, what should be entered in the
electrical log?
a. maximum allowable temperature
b. temperature of machine at the time the
reading is taken
c. the normal temperature rise of the
machine
d. none of these choices
Ans. B
A voltage relay with the addition of an air bleed, or
599. a dashpot to delay the action
of its contacts, is often used for ___________.
a. sequence control
b. acceleration control
c. low voltage release
197
d. all of these choices
Ans. D
Which of the solid AWG wire size has the smallest
600. physical cross-sectional area __.
a. 12
b. 14
c. 16
d. 18
Ans. D
An adjustable resistor, whose resistance can be
601. changed without opening the
circuit in which it is connected is called a/an
__________.
a. bleeder resistor
b. rheostat
c. transistor
d. bridge
Ans. B
The function of a stepdown transformer is to
602. reduce the load _____________.
a. voltage and current
b. voltage and increase line current
c. current and increase line voltage
198
d. power
Ans. B
A loud buzzing noise in an AC controller is
603. probably caused by _____________.
a. poor contact with the overload relay
b. an incorrect sized heater
c. a broken shading coil
d. abnormal starting current
Ans. C
Increasing the load to the secondary windings of a
604. transformer will cause a/an ____.
a. decrease in primary voltage
b. increase in primary voltage
c. decrease in primary current
d. increase in primary current
Ans. D
What is the function of the voltage regulators used
605. with AC generators ?
a. to cut out generators when they are no
longer
199
b. to cut an additional generator automatically
as required
c. to divide the KW load between the two
generators
d. to divide reactive current between generators
operating in parallel
Ans. D
The basic operation principle of a transformer is
606. attributed to _____________.
a. electromagnetic induction
b. variance of a conductor in a magnetic field
c. mutual reaction
d. thermal transmission
Ans. A
Which of the meters listed should be used after a
607. circuit has been electronically
disconnected ?
a. wattmeter
b. frequency meter
c. ammeter
d. ohmmeter
Ans. D
The output voltage of a 440V, 60Hz AC generator
608. is controlled by the _________.
a. load on the alternator
b. load on the prime mover
c. speed of the prime mover
d. exciter output voltage
200
Ans. C
When a transformer is used to step down voltage,
609. the low voltage winding is _____.
a. part of core
b. the primary coil
c. the secondary coil
d. not insulated
Ans. C
Magnetic chatter on “pumping" occurring in a
610. magnetic contactor can be
caused by _____________.
a. dirt or grease in contact surfaces
b. mechanical interference in the contacts
c. chattering contacts on the relay
d. magnetic lockout of the relay
Ans. C
Relative to the secondary winding of a step-up
611. transformer, the primary
winding will have _____________.
a. more turns
b. fewer turns
c. half as many turns
d. twice as many turns
Ans. B
To equalize the power factor of two alternators
612. operating in parallel, the _________.
a. field excitation of both units is adjusted
b. governor of both units are adjusted
c. kilowatt load is evenly divided
201
d. phase sequence is altered
Ans. A
When trouble shooting motor controllers, a
613. shorted relay or contractor coil is
often indicated by _____________.
a. a resistance reading of infinity or an
ohmmeter
b. charred insulation and/or blown control
fuse
c. a reading of zero on a megger
d. a higher than normal voltage reading
Ans. B
You can determine if a circuit breaker is tripped by
614. _____________.
a. examining the position of the handle
b. checking for the warm breaker
c. looking for a burnt out link
d. looking for the tripped breaker light
Ans. A
During maintenance of circuit breakers
615. _____________.
a. always smooth roughened contact surfaces
with a file
b. never pass more than rated breaker current
through the loaded element
202
c. inspect for wear and misalignment of main
contacts
d. assume heater elements installed are of
correct size
Ans. C
Accidental grounds is a shipboard electrical
616. system must be repaired as
soon as possible as they will _________.
a. result in immediate power outages
b. damage circuit breakers
c. appear on the ground detection system
d. damage insulation and may cause
outages
Ans. D
Which of the following statement is TRUE
617. concerning transformer operation?
a. the inductance in the primary side is the same
as the secondary side
b. voltage is the same of primary side and the
secondary side
c. current is the same of primary side and the
secondary side
d. power to the primary side is higher than the
power in the secondary side
Ans. D
A lamp has a source voltage of 110 volts and a
618. current of 0.9 amps. What is the resistance
of the lamp?
a. 0.008 ohm
b. 0.08 ohm
c. 12.22 ohm
203
d. 122.22 ohm
Ans. D
A voltage regulator installed in a direct current
619. generator serves the purpose of ___.
a. varying the shunt field resistance
b. adjusting the cross current
c. lowering the armature circuit resistance
d. limiting the compensating field resistance
Ans. A
Electric motors intended for use outside the
620. engine room are frequently rated to
run at a designed ambient temperature of 40
degrees centigrade. What is the
equivalent temperature in degrees Fahrenheit?
a. 54.2 degrees Fahrenheit
b. 72 degrees Fahrenheit
c. 104 degrees Fahrenheit
d. 129.6 degrees Fahrenheit
Ans. C
A direct current passing through a wire wrapped
621. around a soft iron is a good
example of a simple ___________.
a. magnetic shield
b. electromagnet
c. transformer
d. armature
204
Ans. B
Which of the substances mentioned below can be
622. used to shield sensitive equipment from
static magnetic fields?
a. permeable iron
b. glass
c. varnished cloth0
d. bakelite
Ans. A
The timer element found in a reverse-power relay
623. obtains the operating torque via _________.
a. line voltage
b. the main bus
c. electromagnets
d. a separate battery source
Ans. C
Coast Guard Regulation 46 CFR require each
624. switchboard to have ____________.
a. non-conductive deck covering at the front
b. conductive deck covering at the front
c. a nameplate for each circuit breaker
d. all of these choices
Ans. D
Emergency lightings aboardship should be a/an
625. ______________.
a. illuminated at all times while vessel is
underway
b. illuminated automatically and actuated upon
failure of the main lighting system
205
c. portable battery operated and have sufficient
capacity
d. all of these choices
Ans. B
As per Coast Guard Regulations 46 CFR,
626. emergency generator set aboard
ocean-going vessels must be capable of
supplying emergency lightings for
a minimum period of ______________.
a. 18 hours
b. 36 hours
c. 24 hours
d. 6 hours
Ans. A
As per Coast Guard Regulations 46 CFR,
627. emergency generator fuel tank full
capacity must be capable of supplying the unit for
a period of _____________.
a. 6 hours
b. 18 hours
c. 24 hours
d. 36 hours
Ans. B
As per Coast Guard Regulation 46 CFR, which of
628. the below listed items is the only permissible
starting aid for the emergency diesel generator
engine?
a. ether
b. lube oil heater
c. jacket water heater
206
d. fuel oil heater
Ans. C
The source of emergency lighting and power loss
629. of normal ship's power on a
cargo vessel should be obtained from the
______________.
a. emergency generator supply to the
emergency switchboard
b. emergency generator supply to the main
switchboard
c. battery supply to the main switchboard
d. turbogenerator supply to the emergency
switchboard
Ans. A
An electrical device which employs a stationary
630. armature and a rotating
magnetic field is used aboardship as a
___________.
a. magnetic amplifier
b. ship service generator
c. DC generator
d. saturable core reactor
Ans. B
According to USCG Regulations 46 CFR, how
631. often shall internal combustion
engine driven emergency generators be
operated under load?
a. once a week for 2 hours
b. once a month for 2 hours
c. every six (6) months for 4 hours
207
d. once a week for 4 hours
Ans. B
Note; Ship below 500GRT
The emergency switchboard 24v DC supply is
632. used to provide power to the ______.
a. general alarm system
b. gyrocompass power supply system
c. smoke detection system
d. all of these choices
Ans. D
633. TV station operates at frequencies in the range of
________.
A. 30Mhz to 300Mhz or 50Mhz (VHF)
B. 1700Mhz
C.2400Mhz
D.5Mhz
Ans. A
634. What will be the frequency of a three phase, six
pole A/C generator operating at 1800 revolutions
per minute?
a. 60 Hz
b. 90 Hz
c. 120 Hz
d. 180 Hz
208
PN
Legend:
f=
f = frequency
120
P = Number of poles
N = RPM
6 (1800)
120 = Constant
f=
120
= 90 Hz
Ans. B
635.
TV stations are confined to broad cost in the
frequencies above ______.
a. 5.0 mega Hz
b. 50.0 mega Hz
c. 1,700 kilo Hz
d. 2,400 kilo Hz
Ans. B
636.
What type of motor is NOT suitable for DC
source?
a. Squirrel cage
b. Shunt
c. Series
d. Compound
Ans. A
209
637. What is the approximate voltage per cell
produced by the NICKEL-IRON (Edison) battery?
a. 0.85 volts
b. 1.35 volts
c. 2.20 volts
d. 6.05 volts
Ans. B
638. In order to take a current reading with a
CLAMP-ON-AMMETER, the instrument
jaws_________.
a. should remain open
b. can not touch the adjacent conductor
c. must be fully closed
d. will act as a transformer primary
Ans. C
639.
When securing an AC generator, what procedure
should you follow?
a. reduce the load, trip the circuit breaker, stop the
prime mover speed
b. reduce the load, stop the prime mover speed, trip
the circuit breaker
c. trip the circuit breaker, reduce the load, stop the
prime mover speed
210
Ans. A
640.
The ability of a material to RETAIN SMALL
AMOUNT OF MAGNETISM or MAGNETIC LINES OF
FORCE when the magnetizing force is removed.
a. retentivity
b. magnetically saturated
c. residual magnetism
Ans. A
641.
One advantage of AC generator over DC
generator is that___
a. No sparking at the brushes
b. No overheating
Ans. A
642. Periodic testing of circuit breakers is necessary to
assure that a correctly rated and properly
installed unit _______.
A. Can trip faster as it increases in age
B. Will continue to provide the original degree of
protection
C.Does not exceed its interrupting capacity
D.Be able to withstand at least 125% of applied
voltage
211
Ans. B
643. What is the purpose of fuse place in series with a
thermal trip type circuit breaker?
A. Time-delay protection
B. Short circuit protection
C.Short duration surge protection
D.Sustained overload protection
Ans. B
644. The engine starting fuel setting/metering of the
governor is usually set at _______.
A. Dead slow ahead
B. Slow ahead
C.Half ahead
D.Between slow and half ahead
Ans. D
645. Some materials are neither good conductors nor
good insulators since their electrical characteristic
fall between those of conductors and insulators.
These in between materials are known as _____.
A. Semi-conductors
B. Semi-metals
C.Solid-state devices
D.Semi-insulators
Ans. A
212
646. An inspection which is in regular intervals is
called a/an _______.
A. Periodic inspection
B. Preventive maintenance inspection
C.Regular maintenance inspection
D.Initial inspection
Ans. A
647. Which of the following types of motors is often
designed for use in correcting power factor?
A. Polyphase
B. Wound-rotor
C. Induction
D. Synchronous
Ans. D
648. Failure in the mechanical governor spring will
result in _______.
A. Increase in engine speed
B. Decrease in engine speed
C. Governor to hunt
D. Will not affect the engine
Ans. B
649. Most electronic device/parts is constructed of __.
A. Copper
213
B. Gold
C.Silver
D.Matter
Ans. C
650. The air gap in an induction motor should be
periodically checked with feeler gauge to prevent
possible.
A. Rotor contact with the stator/rotor clearance
B. Loaded alternator is turning faster than the
incoming machine
C. Damaged to the motor bearings
Ans. A
651. If a speed of an engine fitted with isosynchronous
governor suddenly increases, after compensation
is performed by the governor, the engine speed
will _________.
A. Remain the same
B. Increase
C. Decrease
D. None of these
Ans. A
214
652. Two base material used in semi-conductors are
silicon and _______.
A. salt
B. gemanium
C. diode
D. transistor
Ans. B
653. What is the simplest way of voltage regulation?
A. Zener diode
B. Transistor
C. Resistor
D. Capacitor
Ans. A
654. The most outstanding characteristics of a Zener
diode is that, even current changes widely, it is
constant in ________.
A. Load
B. Voltage
C. Frequency
D. Power
Ans. B
215
655. Most part of engine system is composed of two
alarms. Which of the following system consisting
a single alarm only?
A. Low lube oil pressure
B. Low lube oil sump tank
C. High jacket cooling water temperature
D. High main bearing temperature
Ans. A
Note;
Only Lube oil pressure alarm consist a single
alarm, because this automatically shutdown the
engine. While sump tank level consist of low level
and low-low level alarm, jacket water and main
bearing temperature consist of high temp. and
high-high temp (slowdown) alarms.
656. Diesel engine automated control system may
utilize sensing devices of dual function, with
sensing ranges providing both alarm & engine
shutdown capability. Which of the key points
listed below would require only an alarm sensor?
A. Engine overspeed
B. Lube oil sump low level
C. Lube oil pressure low
D. Main bearing temperature high
Ans. B
Note;
Sump tank level consist only of alarms such as
low and low-low level alarm. While engine
overspeed and lube oil press. alarm consist of an
alarm and shutdown. Then Main bearing
temperature consist of an alarm and slowdown.
216
657. Which of the listed logic gates is considered to be
a BASIC building block used in logic diagrams?
I – NAND
II – OR
III – NOR
A. I only
B. II only
C. III only
D. All of these
Ans. B
658. Which device/machine designated to operate
without the use of commutator & brushes?
A. Brushless AC generator
B. Brushless DC generator
C. Slip ring AC generator
D. Slip ring DC generator
Ans. A
659. Routine maintenance of lead acid batteries
should include ______.
A. Keeping the terminals clean
B. Coating cable connections with petroleum jelly
C. Maintaining a trickle charge
D. All of these
Ans. D
660. The transmit & receive elements of a soundpowered telephone handset are ________.
217
A. Identical & can be used for either function
B. Of similar construction but different enough to
be used only of its own function
C. Of very different construction & must be
used only for its own function
D. Constructed so that each can fit only in its
own recess
Ans. A
661. A continuous fluctuation of the governorcontrolled speed is known as _______.
A. hunting
B. droop
C. sensitivity
D. stability
Ans. A
662. When working on a high voltage circuit, you
should always have another person present with
you. This person should have a good working
knowledge of _________.
I – The circuit being worked on & the location of
all switches & circuit breakers controlling it
II – First aid techniques for treating electrical
shock
III – Cardiopulmonary resuscitation (CPR)
A. I only
B. II only
C. III only
D. I, II & III
Ans. D
218
663. Which of the following statements about a threephase wye connection is correct?
A. The line current is 1.73 times the phase current
B. The phase current is 1.73 times the line current
C. The line voltage is 1.73 times the phase
voltage
D. The phase voltage is 1.73 times the line
voltage
Ans. C
664. The need for insulation cleaning may be
determined by _____.
A.
B.
C.
D.
Visual inspection for dirt accumulation
High megger readings
Low operating temperature
The time period since the last cleaning
Ans. A
665. Periodical testing by a shoreside support using a
special camera which can detect potentially
dangerous loose or corroded bus bar & controller
connections is termed _______.
A.
B.
C.
D.
Heat sensitive thermography
Visual pyrotronics
Corrosion electrolysis
Electric vibroanalysis
Ans. A
219
666. You have installed a Zener diode in parallel with
the load. While measuring the voltage across the
Zener it is found that it does not change as the
current through load increases which means
____.
A.
B.
C.
D.
is working as it should
is shorted
is open
does not regulate as it should
Ans. A
667. The basic control action of an magnetic amplifier
depends upon ____.
A.
B.
C.
D.
Variations in the load capacitance
Changes in inductance
Type of core material
Construction of the core
Ans. B
668. When a ship service generator equipped with
centrifugal type hydraulic governor load
increases, what action will occur in the governor
internal mechanism?
A.
B.
C.
D.
Weigh will move inward
Lifting will have inward
Pilot valve bushing is lowered
Oil is pumped into the cylinder
Ans. C
669. If only one brush on a commutator is sparking
excessively, you should look for _______.
220
A.
B.
C.
D.
A high commutator bar
Copper imbedded in the brush
A loose commutator bar
Flux in the commutator zone
Ans. B
670. The rated temperature rise of an electric motor is
the ________.
A. Average temperature at any given latitude
B. Normal temperature rise above the
standard ambient temperature at rated
load
C. Average temperature at rated load
D. Permissible difference in the ambient
temperature of the motor due to existing
weather condition
Ans. B
671. The heat required to changed a substance from a
solid to a liquid while at its freezing temperature,
is known as the latent heat of ________.
A.
B.
C.
D.
fusion
vaporization
condensation
sublimation
Ans. A
672. What is placed in a circuit for current to flow in
one direction only?
A. Transformer
B. Capacitor
221
C. Transistor
D. Diode
Ans. D
673. Charge bodies attract or repel each other is in
what law?
A.
B.
C.
D.
Magnetism law
Ohm’s law
Electromagnet law
Kirchoff’s law
Ans. A
674. What law that describes how the materials attract
& repel when ENERGIZED?
A.
B.
C.
D.
Magnetism law
Ohms law
Electromagnet law
Kirchoff’s law
Ans. C
675. When a transistor has very and almost equal
forward & reverse resistance between its emitter
& base leads, the device is ________.
A.
B.
C.
D.
good
grounded
bad
shorted
Ans. D
676. If atom loses an electron and has an overall (+)
positive charge, it becomes ______.
222
A.
B.
C.
D.
Light atoms
+ ion
Fast moving atoms
Slow moving atoms
Ans. B
677. Which of the combustion parameters listed is
used in a diesel engine, but NOT related to the
injection system?
A.
B.
C.
D.
Atomization
Metering
Effective stroke
Penetration
Ans. D
678. Which of the listed governor operating
characteristics is considered to be isochronous?
A.
B.
C.
D.
Zero speed droop
Positive speed droop
Negative speed droop
Varying speed droop
Ans. A
The full torque electric brake on an electric cargo
679. winch functions to ___.
a. act as a backup brake in case the mechanical
brake should fail
b. automatically hold the load as seen as
223
current to the machine
is shut off
c. automatically reduce lowering speed
d. automatically reduce hoisting speed
Ans. B
Moisture damage due to consideration inside the
680. cargo winch master
switches can be reduced by _____________.
a. installing light bulb in the pedestal stand
b. sealing the switchbox
c. venting the switchbox regularly
d. using strip heaters inside the switch box
Ans. D
In the event of a power failure during cargo
681. loading operations, the
movement of an electric powered cargo will be
stopped by ______.
a. manual override switch
b. spring set brake
c. hand-operated brake
d. weight of the boom load
Ans. B
The greatest enemy of an idle electrical
682. equipment such as a pump
room fan motor is the _____________.
a. loss of magnetism
b. moisture in the insulation
c. insulation varnish flaking
d. dirt accumulation on the windings
Ans. B
224
Which of the following represents the best method
683. of cleaning dust from
electrical circuits in order to limit damage to
electronic components?
a. wipe off with soft cotton rag
b. use high velocity compressed air
c. use vacuum cleaner
d. use chemical solvent
Ans. C
In an induction motor, rotor currents are circulated
684. in the rotor by ____.
a. slip ring and brushes
b. armature and brushes
c. inductive reaction of rotating stator field
d. external variable resistor
Ans. C
A circuit breaker and a fuse have basic similarity
685. in that they both ____.
a. can be reset to energize the circuit
b. should open the circuit when overload
develops
c. will burn out when overload develops
d. all of these choices
Ans. B
Electrical leads and insulation on a motor should
686. be painted with ___.
a. heat resisting acrylic
b. heat resistant aluminum
c. insulating varnish
225
d. insulating white lead
Ans. C
A degree of control over speed of slip ring
687. induction motor
can be obtained by _______.
a. adjusting governor linkage
b. changing the number of coils on the motor
c. inserting assistance to the stator
d. inserting resistance to the rotor
Ans. D
A circuit breaker differs from a fuse because a
688. circuit breaker can ___.
a. melt and be replaced
b. enclosed tube has insulating material
c. gives no visual condition
d. trips to break the circuit and my be reset
Ans. D
The main purpose of an auxiliary windings as a
689. split-phase,
single-phase motor is to____.
a. limit the starting voltage
b. increase starting current
c. start the motor
d. keep the motor running
Ans. C
The state of charge of a lead acid storage battery
690. is best
indicated by _____________.
a. testing individual cell voltages
226
b. ampere hour capacity
c. specific gravity of electrolyte
d. total cell voltage
Ans. C
A low voltage source is being used for testing
691. armature coils. A short
circuit will be indicated by a _____________.
a. high voltage reading
b. zero or low voltage reading
c. fluctuating voltmeter reading
d. steady voltmeter reading
Ans. B
Which of the listed procedures should be carried
692. out to prevent moisture
damage to idled electrical apparatus?
a. inert the space
b. strap silica gel
c. place heat lamps
d. cover the equipment with canvass
Ans. C
Electric heaters are used in motor controllers to
693. _____________.
a. prevent movable contacts from freezing
b. keep components warm
c. prevent condensation of moisture
d. maintain good resistance of circuit
Ans. C
A fuse that blows often should be replaced only
694. with fuse of _______.
227
a. recommended current and rating
b. higher current and rating
c. lower current and rating
d. none of these choices
Ans. A
Which of the listed precautions should be
695. observed before spraying
liquid solvent on the insulation of an electric
motor?
a. slow the motor down to low speed
b. disconnect the motor from the power source
c. secure all ventilation in the area
d. pre-heat the insulation
Ans. B
On a tanker vessel with electrically driven
696. capstan, the motor should
be megged periodically to test _____________.
a. insulation resistance
b. eddy currents
c. capacitance
d. armature reactance
Ans. A
A reverse power current relay prevents AC
697. generator motorization
automatically by ___.
a. transferring the load
b. speed up the prime mover
c. secure the exciter generator
d. tripping the circuit breaker
Ans. D
228
Which of the following devices will prevent an AC
698. generator from
becoming motorized?
a. overcurrent relay
b. relay trip
c. governor control
d. reverse current/power relay
Ans. D
699. A grounded switch or cable will be indicated by a
megohmeter of _____________.
a. infinity
b. zero
c. unsteady reading in high range
d. unsteady reading in low range
Ans. B
Batteries used for diesel engine starting should
700. _____________.
a. be located in a locker on the weather deck
b. be located as close as possible to the
engine
c. have capacity to start the engine up to 50
times
d. none of these choices
Ans. B
Before testing insulation with a megohmeter, the
701. windings of large
machines should be grounded for 15 minutes
because ___________.
a. static charge in the machine may give false
229
reading
b. insulation may get damaged
c. insulation may be wet
d. machine may run automatically
Ans. A
Battery charging rooms should be well-ventilated
702. because the
charging process _____.
a. produces highly poisonous hydrogen
b. produces highly combustible oxygen
c. liberates explosive gases
d. liberates corrosive gases
Ans. C
When a megger is used to test insulation, the
703. gradual rise of the pointer
reading as a result of continued cranking, is
caused by ___________.
a. good resistance
b. leakage in the winding
c. inductive resistance in windings
d. dielectric-absorption effect of the insulation
Ans. D
Most 3-phase induction motors for driving engine
704. room auxiliaries
are started by ______.
a. resistor starters
b. across-the-line starters
c. impedance starters
d. reactor starters
Ans. B
230
First aid treatment for battery acid or alkali burns,
705. especially in the
eyes, includes ______.
a. flushing with large amounts of fresh water
b. wiping the affected area with clean dry cloth
c. using talcum powder to counter itching
d. all of these choices
Ans. A
A hydrometer is used to measure
706. _____________.
a. specific gravity of battery electrolyte
b. water pressure on deck line
c. amount of distilled water evaporator
produced
d. power developed by sea water service
pump
Ans. A
Discharge switches are often located on hand707. driven meggers. The
purpose of these switches is to discharge
capacitive charges
stored in the _______________.
a. megger hand generator
b. movement coils
c. tested equipment while conducting test
d. tested equipment after conducting test
Ans. D
A megohmmeter can be used to test for
708. _____________.
231
a. an open field
b. synchronous speed
c. frequency
d. high voltage prsence
Ans. A
You are attempting to parallel two AC generator
709. and the synchroscope
pointer is revolving slowly in the fast direction. You
should ________.
a. use the governor switch to adjust incoming
voltage so it is equal
to the voltage
b. use the governor switch to increase the
speed of the prime mover
c. close the circuit breaker when the
synchroscope pointer approaches
“0” position
d. close the circuit breaker when the
synchroscope pointer approaches
“180” position
Ans. C
A fuse will blow for all the listed reasons except
710. _____________.
a. excessive vibration
b. extremely hot surroundings
c. loose fuse clips
d. low contact resistance within the fuse
Ans. D
Moisture absorbed in the windings or condensed
711. on the surface of
electrical machinery insulation _____________.
232
a. is good for the machinery as additional
insulation
b. lowers insulation value and may create
grounds
c. enhance insulation value of the machine
d. reduce the amount of current to be fed to the
machine
Ans. B
In which of the situation listed will a megohmmeter
712. give the most
accurate reading ?
a. while the machine is in operation
b. while the machine is about to stop
operation
c. immediately after the machine has stopped
d. 15 minutes after the machine has been
isolated and grounded
Ans. D
When using a multimeter for resistance
713. measurements, it should be
calibrated by clipping the loose ends of the leads
together and ____.
a. setting the instrument pointer at zero ohms
b. adjusting the line voltage to calibrate the
instrument
c. plugging each end of one test lead into the
plus and minus terminals
d. using special purpose resistance measuring
instruments
Ans. A
Which of the following insulation will deteriorate
714. first as a result of heat
233
generated in the conductor it surrounds ?
a. rubber
b. varnished cloth
c. silicon
d. asbestos
Ans. A
A multimeter can be used to measure
715. _____________.
a. resistance
b. voltage
c. current
d. all of these choices
Ans. D
Which of the following problems will most likely
716. occur if the starting
winding of a split-phase induction motor failed to
cut-out once the
motor was in continuous operation?
a. the motor will overspeed
b. the motor will run at a reduced speed
c. the motor will stop
d. the winding will burn out
Ans. D
When insulation failure produces a low resistance
717. current path between
two conductors, the resulting condition is known
as _____________.
a. an open circuit
b. a short circuit
c. a ground
234
d. a surge
Ans. B
When disassembling motor for maintenance or
718. overhaul _________.
a. punch mark frame and end bells for proper
assembly
b. wrap bearings in lint free cloth if they are to
be reversed
c. tag and store small parts in a box
d. all of these choices
Ans. D
719. Fuses are usually rated in _____________.
a. watts
b. amps only
c. volts only
d. amps and volts
Ans. D
When used for taking resistance measurements,
720. voltage-ohmmeter is
normally paired by _____________.
a. a hand cranked generator
b. internal storage batteries
c. the current in the circuit being tested
d. a step-down transformer
Ans. B
When an AC or DC motor fails to start, the FIRST
721. step in troubleshooting
should be to check the _____________.
a. motor windings for obvious opens
235
b. motor controller leads for continuity
c. fuse or circuit breaker
d. motor controller leads to ground
Ans. C
A current-carrying conductor making electrical
722. contact with a wiring conduit
will be indicated by a _____________.
a. high switchboard wattmeter reading
b. totally dark switchboard ground detecting
light
c. low switchboard wattmeter reading
d. all of these choices
Ans. B
To remove an alternator operating in parallel with
723. mother unit from the main
electrical bus, you must FIRST _____________.
a. adjust the power factor on both units
b. set the desired voltage on the outgoing
alternator
c. open the circuit breaker on the outgoing
alternator
d. remove the load from the outgoing
alternator
Ans. D
When testing for blown fuses in a three-phase
724. supply circuit to a motor,
you should first _____________.
a. apply the megger across the tops of the line
fuses
b. apply the megger across the bottom of the
line fuses
236
c. apply the voltage faster across the bottom of
the line fuses
d. de-energize the circuit and then use a
continuity tester
Ans. D
In a three-phase electrical system, three ground
725. detecting lamps are provided.
If all three lamps REMAIN at half brilliance when
the ground detecting
switch is operated _____________.
a. there is a slight ground on all three phases
b. the switch must be replaced
c. there are no grounds present
d. the light bulbs are of improper voltage
Ans. C
Electrical failures in motors are caused by the
726. breakdown of insulation,
which maybe caused by _____________.
a. penetration of moisture
b. accumulation of dirt
c. overheating
d. all of these choices
Ans. D
In order to safely carry out repairs to a generator
727. circuit breaker, it must be
isolated from the bus. This is accomplished by
opening the ________.
a. reverse power relay
b. bus disconnect link
c. generator bus fuse connection
d. power directional relay
237
Ans. B
If the voltage supplied to the lightning circuit is 110
728. volts. How much
current is used by a 100 watt light bulb ?
a. 0.08 amps
b. 0.91 amps
c. 1.10 amps
d. 90.9 amps
Ans. B
According to USCG regulation (CFR 46) which of
729. the ff systems must be
arranged so as to be energized by emergency
power supply in case of
power failure?
a. at least one light is steering gear room
b. each power operated watertight door
system
c. each changing panel for temporary
emergency batteries
d. all of these choices
Ans. D
Diesel generator # 1 & 2 are operating in parallel
730. at near full load capacity.
Diesel generator # 1 suddenly trips out
mechanically due to low lube oil
pressure. The reverse power relay functions
properly and trips generator
# 1 off the board. Which of the following should
you do FIRST?
a. start the standby generator
b. ascertain cause of low lube oil pressure
238
c. strip the board of non-vital loads
d. secure alarm, reset all tripped relays and
restart generator # 1
Ans. C
The source of emergency lightning and power at
731. loss of normal-ship’s
power on a cargo vessel should be obtained from
the _____________.
a. emergency switchboard
b. main switchboard
c. emergency batteries
d. emergency power from main switchboard
Ans. A
International regulations states that continuous
732. trickle charge supplied
from the ship’s required service power system, is
for batteries supplying
power to the __________.
a. emergency diesel starting system
b. emergency power system for radar
c. emergency power system for steering gear
d. emergency power system for lifeboat radios
Ans. A
According to USCG Regulation 46CFR, the the
733. talking and calling circuits
of a sound powered telephone system must be
__________.
a. intrinsically safe
b. independent of each other
c. independently grounded
d. connect to a common ground
239
Ans. B
Which of the listed safety features should be
734. provided in a small room or locker
where batteries are stored?
a. install a CO2 system
b. install an exhaust system fan
c. an exhaust duct to be made 3 feet above
the deck
d. exhaust duct is to be provided from the top of
the locker to open air
Ans. D
You should not allow salt water to enter a lead
735. acid battery or come in contact
with sulfuric acid because _____________.
a. resulting gas is extremely flammable
b. the resulting gas is a respiratory irritant that
can be fatal
c. the primary constituent, sodium, reacts
lethally with lead peroxide
d. continuing salt water with lead acid creates a
harmful gas
Ans. B
Which of the ff should be done when a 10 amp
736. blown fuse is replaced ?
a. short out the fuse
b. replace blown fuse with less than 10 amp
rating
c. replace blown fuse with exactly 10 amp
rating
d. none of these choices
240
Ans. C
International Regulations requires that an
737. indicating light at the
propulsion control station will activate if
overloading or overheating
occurs in a ____________.
a. forced draft fan
b. steering gear motor
c. fuel pump motor
d. condensate pump motor
Ans. B
International regulations requires that a remote
738. stop/start button for
engine room bilge pump shall be located at
_____________.
a. main deck / upper deck
b. emergency generator room
c. engine control room
d. cargo control room
Ans. A
International regulations requires a continuous
739. trickle charge is to be
applied from the ship’s service power system for
batteries
supplying power to the ___________.
a. emergency power for bridge and engine
control rooms
b. portable radios fro the lifeboat
c. emergency power and lightings
d. all of the above
Ans. C
241
A multimeter may be damaged by taking a
740. _____________.
a. voltage reading while in the resistance
mode
b. current reading while in voltmeter mode
c. resistance reading while in the ammeter
mode
d. resistance reading while in the voltmeter
mode
Ans. A
When replacing fuses, always make sure
741. _____________.
a. to stand on a rubber mat and use rubber
gloves
b. to use insulated pliers or screwdrivers
c. the fuse clips are straight, tight and holding
the new fuses well
d. to increase the fuse rating by 1-% to guard
against “nuisance” blowing
Ans. C
If all the grounds lamps burn with equal brilliance,
742. whether the test button
is depressed and released, which of the listed
conditions is indicated?
a. no ground exist
b. all three phases are grounded
c. the test switch is faulty
d. the current transformers are shorted out
Ans. A
743. The ground indicating light on the main
242
switchboard is indicating a ground.
The last procedure for locating the grounded
circuit is to ____________.
a. trace the circuit’s paths while looking for
burned spots
b. open the circuit breakers on the distribution
panel one by one until the
lights no longer indicate a ground
c. check circuits for continuity
d. none of these choices
Ans. B
An ohmmeter can be used to test for
744. _____________.
a. an open field coil
b. a shorted field pole
c. reverse polarity
d. low voltage supply
Ans. A
Electrical machinery insulation will breakdown
745. more rapidly due to ________.
a. low loading of motor and generators
b. frequent megger testing
c. high temperature and vibration
d. high operating frequencies
Ans. C
Low horsepower, poly-phase conduction motors
746. can be started with full
voltage by means of _____________.
a. compensator starters
b. auto transformer starters
243
c. across the line starters
d. primary resistor starters
Ans. C
Which of the following conditions will occur if the
747. solenoid coil burns out
on a cargo winch with an electric brake ?
a. the brake will be set by spring force
b. the motor will overspeed and burn out
c. the load suspended from the cargo boom
will fall
d. none of these choices
Ans. A
External shunts are sometimes used with
748. ammeters to _____________.
a. increase meter sensitivity
b. prevent shunts with larger resistance to be
utilized
c. prevent damage to the meter movement from
heat generated by the shunt
d. enable the construction of a compact meter
with a virtually unlimited range
Ans. C
Which of the following statements is correct in the
749. maintenance of
contacts in relays ?
a. they should dressed with wire wheel
b. they should be dressed w/ fine cut file if
surface is uneven
c. if burns are noticed, at should be removed w/
sandpaper
d. should be held together with every paper
244
driven between contacts
Ans. B
A signal derived from a controlled function and
750. returned to the initiating point
is called a/an _____________.
a. monitoring signal
b. inverse signal
c. reverse signal
d. feedback signal
Ans. D
A device which prints out a permanent record of
751. the plant operating
conditions is known as the _____________.
a. analog logger
b. bell book
c. alarm logger
d. data logger
Ans. D
The speed of squirrel cage induction motor is
752. determined by the _______.
a. diameter of the stator
b. no. of stator poles
c. rotor winding resistance
d. stator winding resistance
Ans. B
Under which of the listed conditions can the
753. engine room retake the
throttle control from the bridge ?
a. anytime it deemed necessary
245
b. only w/ master’s permission
c. after 10 min. delay to the command
d. only when the throttle is at stop
Ans. A
A generator has been exposed to water and is
754. being checked for its safe
operation. Therefore it is necessary to
________.
a. check for shorted coils
b. take moisture reading
c. test insulation reading
d. ground the commutator and run it for half an
hour
Ans. C
A squirrel-cage motor is designed to have
755. _____________.
a. low starting voltage
b. low starting current
c. high starting voltage
d. low starting resistance
Ans. B
In a DC series circuit, all the conductors have the
756. same _____________.
a. power consumption
b. voltage drop across
c. current passing thru them
d. resistance passing thru them
Ans. C
757. Which of the AWG wire sizes listed below would
246
have the smallest diameter ?
a. 000
b. 0
c. 12
d. 250
Ans. C
When using a megger to test insulation, good
758. insulation will be
indicated by ______.
a. slight kick of the needle downscale
b. downward dip followed by gradual climb to
the true resistance value
c. initial dip of pointer
d. gradual rise in the pointer
Ans. B
A reverse-current relay will prevent DC generator
759. motorization by _______.
a. automatically redirecting the load
b. automatically speeding up the prime mover
c. tripping the panel board main switch
d. tripping the generator circuit breaker
Ans. D
If many turns of an alternating current coil
760. contractor become short
circuited, the coil ___.
a. temperature will drop
b. will probably burn out completely
c. will continue to operate
d. will operate on reduced current
247
Ans. B
How is a wattmeter electrically connected in a
761. circuit ?
a. in series
b. in parallel
c. in series-parallel
d. inductively
Ans. C
Which of the listed conditions would indicate the
762. need for cleaning
electrical insulation ?
a. low ambient temperature
b. low operating temperature
c. high dielectric strength
d. low megger readings
Ans. D
A multimeter maybe damaged by taking a
763. _____________.
a. voltage reading while in the ammeter mode
b. current reading while in the voltmeter mode
c. resistance reading in the ammeter mode
d. resistance reading in the voltmeter mode
Ans. A
Multiple grounds have developed and were initially
764. indicated by the
ground detecting system as one ground. The first
step in locating
ground is to _____________.
a. examine the main bus bars for signs of
248
overheating
b. eliminate the individual circuits one by one
until te ground detecting
system no longer indicates any grounds
c. change over generators
d. check each circuit with a megohmeter
Ans. B
To protect the rotor of a motor disassembled for
765. maintenance or
overhaul, it should be _____________.
a. suspended by wire slings in one corner of
the shop
b. wrapped it with heavy papers or lint free
cloth
c. support by flat wood blocks on the
workbench
d. return to the frame as soon as the bearing is
removed
Ans. B
Which of the following material is a good
766. insulator ?
a. glass
b. steel
c. aluminum
d. copper
Ans. A
Which of the conditions listed below will indicate
767. the need to clean the
insulation on the windings of an electric motor?
a. higher than normal operating temperature
b. excessive vibration at normal speed
249
c. sparking at the brushes
d. high megger readings
Ans. A
If all the ground detection lamps burn with equal
768. brilliance, whether
the test button is depressed or released, then
________.
a. no ground exist
b. all phases are grounded
c. all lamps show a ground
d. all of these choices
Ans. A
If the energy input is significantly reduced to the
769. prime mover of one
shipboard alternator operating in parallel with
others, that alternator will ___.
a. continue to operate at no load
b. lose its load and overspeed
c. begin to motorize and then trip out
d. slow down and operate at reduced load
Ans. C
The failure of ball bearings used in electric motors
770. can result from ________.
a. failure to clean the bearing before repacking
b. failure to maintain proper alignment
c. excessive grease in bearing thus eliminating
room for expansion
d. all of these choices
Ans. D
250
Which of the listed condition will occur if dirt and
771. grease are allowed
to accumulate between the commutator segments
of a motor?
a. partial short circuit
b. a dead short circuit
c. misalignment of the motor shaft
d. overspeeding of the motor
Ans. A
A damp armature windings in an AC motor may
772. lead to _______________.
a. reduced voltage
b. reduced current
c. Increased resistance
d. overheating
Ans. D
A single-phase induction motor starts, reaches
773. 75% rated speed,
slows down and accelerates again. The problem
is most likely in the _____.
a. starting winding
b. running winding
c. starting capacitor
d. running centrifugal switch
Ans. B
On large generators, space heaters are used to
774. _______________.
a. keep the machine at ambient temperature of
the machinery space
b. maintain motor parts above dew point to
251
prevent condensation
c. prevent condensation on the bearings
d. prevent stack up of rotating parts
Ans. B
If a brush on a DC generator is only partially
775. seated, which of the following
problems may occur?
a. high current density developing at the contact
surface
b. continual overheating at the brush line
c. the brush will spark during the operation of the
generator
d. all of these choices
Ans. D
Most conducting materials such as copper,
776. aluminum, iron, nickel
and tungsten ______.
a. increase in resistance with increased
temperature
b. increase in resistance with decreased
temperature
c. decrease in resistance with increased
temperature
d. increase in conductance with increased
temperature
Ans. A
Electric motor ball bearings designed to be filled
777. with grease should
have the relief plug temporarily renewed while
grease is
being added. This plug should remain out until the
machinery has
252
been operated and warmed up to ensure that
__________.
a. a path of expansion is provided for the
grease
b. all air pockets are vented from the grease
c. dirt and grit are flushed from the bearing
house
d. the grease is properly distributed within the
bearing
Ans. A
A large generator is provide with a space heater to
778. ________________.
a. keep the machine at ambient temperature of
the machinery space
b. maintain rotor and stator winding temperature
above dew point
c. prevent condensation in the lube oil
d. prevent electrolysis due to condensation in the
bearings
Ans. B
If air gap readings from an electrical generating
779. machine have changed
significantly from the last reading, you should
check __________.
a. the bearings
b. insulation readings and machine cleanliness
c. prime movers thrust bearing
d. the field coil bolts for proper tightness
Ans. A
Routine AC motor maintenance should include
780. periodic ____________.
253
a. temperature readings at normal loads to
detect abnormal temperature rise
b. inspection of motor internals for loose rotor
bars
c. verifying the RPM is within normal range
d. all of these choices
Ans. A
When removing ball or roller bearings from the
781. shaft of a motor, you should use a ___.
a. rawhide hammer
b. brass mallet
c. wheel puller
d. soft iron pry bar
Ans. C
A circuit that has one of two wires in contact with
782. the hull of a ship is called a_______.
a. grounded circuit
b. short circuit
c. series circuit
d. closed circuit
Ans. A
Encrusted dirt accumulated inside a motor should
783. be removed with a _________.
a. fiber scrapper
b. painted welding rod
c. hammer and chisel
d. paint scraper
Ans. A
784. Silicone diodes designed for a specific reverse
254
breakdown voltage, become
useful as an electronic power supply voltage
regulator is called ________________.
a. tunnel diodes
b. hot-carrier diodes
c. compensating diodes
d. zener diodes
Ans. D
Which of the listed devices may be used as a
785. digital device?
a. variable resistor
b. diode
c. strain gauge
d. thermistor
Ans. B
Which of the listed condition is an advantage of a
786. PN diode over a vacuum diode?
a. longer life
b. no warm up time
c. less delicate
d. all of these choices
Ans. D
Heat sinks are frequently used with
787. _____________.
a. power transistors
b. vacuum tubes
c. tunnel rectifier diodes
d. all of these choices
Ans. A
255
A semiconductor is a material with a
788. _______________.
a. conductivity higher than a normal conductor
b. conductivity higher than a normal insulator
c. high conductivity at low temperature
d. low conductivity at high temperature
Ans. B
Which of the listed conditions describes the effect
789. on intrinsic semiconductor
operation as a result of a temperature increase?
a. capacitive reactance will decrease
b. conductivity will increase
c. inductive reactance will decrease
d. resistivity will increase
Ans. B
Brushless generators are designed to operate w/
790. out the use of _____________.
a. brushes
b. slip rings
c. commutator
d. all of these choices
Ans. D
On a diesel electric plant, raising the generators
791. field excitation will cause the
DC propulsion motor to _____________.
a. increase in speed
b. decrease in speed
c. affect the generator speed only
d. affect the main motor speed
256
Ans. A
Electric propulsion coupling excitation is reduced
792. at slow speeds to_____________.
a. increase speed control
b. increase shaft torque
c. prevent coupling from overheating
d. prevent coupling from slippage
Ans. C
793. When choosing a battery for a particular
application, major consideration
should be given to the battery’s _____________.
a. ampere hour capacity
b. terminal polarity
c. stability under changes
d. ambient temperature rise
Ans. A
An electrical device w/c employs a stationary
794. armature and a rotating
electromagnetic field is used aboard ship as a
___________.
a. magnetic amplifier
b. ship service alternator
c. three-wire generator
d. saturable reactor
Ans. B
A lead-acid battery is considered fully charged
795. _____________.
a. when the electrolyte is gassing
b. ammeter indicates positive reading
257
c. terminal voltage reaches constant value
d. specific gravity no longer increases 1 to 4
hours
Ans. D
Electrical circuits are protected against
796. overheating by means of a/an _______.
a. circuit breaker
b. amplifier
c. diode
d. capacitor
Ans. A
Which of the following electrical properties will be
797. the same with respect to
each component in series circuit?
a. voltage
b. current
c. resistance
d. inductance
Ans. B
Which of the following components are used to
798. convert AC to DC?
a. armature and equalizer
b. commutator and brushes
c. rotor and interpoles
d. field excitation
Ans. B
Line loses in a distribution circuit are kept to a
799. minimum by _____________.
a. adding rubber insulation in the circuit
258
b. using high current and low voltage
c. increase boosters in the line
d. using higher voltage and low current
Ans. D
To minimize magnetic field excitation between
800. electrical conductors in physical
proximity, it is best to keep them
_____________.
a. parallel and as close as possible to each
other
b. at right angles with each other
c. parallel and far away from one another
d. at right angles and as far away as practicable
for one another
Ans. D
As insulation resistance reading is taken at 20
801. degrees Celsius and found to be
10 megohms. What would expect the resistance
reading
a. 2.5 ohms
b. 10 ohms
c. 15 ohms
d. 20 ohms
Ans. A
The amount of current flow required for the
802. cathodic protection of a vessel is
dependent upon the _____________.
a. amount of bare steel surface
b. speed of the ship through water
c. temperature of the water
d. all of these choices
259
Ans. D
When paralleling two AC generator, which of the
803. following actions should be
the final step?
a. adjusting the governor
b. balancing the load
c. closing the circuit breakers
d. closing the equalizing switch
Ans. B
Which type of AC single-phase motor will also
804. operate on DC ?
a. split-phase
b. series-wound
c. shaded pole
d. repulsion-start
Ans. B
The standard procedure for maintaining the
805. charge in a battery is
to trickle charge _____________.
a. continuously
b. at least once a week
c. whenever the charge falls below 75%
d. whenever the specific gravity falls below 1.2
Ans. A
A lead acid battery may become hotter than
806. normal during a charge if the _______.
a. battery has shorted cell
b. charging voltage is low
c. specific gravity is too high
260
d. battery room door is secured
Ans. A
Before touching a small capacitor connected to
807. de-energize circuit, or even the
one that is completely disconnected, one should
_______________.
a. tap it with screwdriver
b. use a de-energise tag
c. use a puller
d. short circuit the terminal
Ans. D
Kilowatt load is divided between two AC
808. generators operating in parallel by _______.
a. adjusting the governor control
b. varging the excitation voltage
c. increase prime mover speed
d. decrease prime mover speed
Ans. A
In a simple series circuit, the entire source voltage
809. will drop across _____________.
a. the resistor next to the negative terminal
b. a short circuit
c. an open circuit
d. resistor next to the terminal
Ans. C
Excessive heat in an operating motor controller
810. can result from _____________.
a. a closed starter contact
b. loose connection
261
c. missing arc chute
d. low motor starting torque
Ans. B
An ammeter should be used to measure
811. _____________.
a. the voltage between two points in a circuit
b. circuit continuity
c. current flow in a circuit
d. total or partial circuit resistance
Ans. C
What is the approximate voltage per cell produced
812. by the nickel-iron battery?
a. 0.25 volts
b. 1.35 volts
c. 1.5 volts
d. 6.0 volts
Ans. B
Which of the methods listed below is used to start
813. an AC generator turning?
a. residual magnetism remaining in the field
poles
b. residual magnetism remaining in the field
coils
c. residual magnetism remaining in the
armature
d. none of these choices
Ans. D
A handheld digital tachometer could give a bad
814. reading if _____________.
262
a. aimed directly at the shaft
b. partially aimed at the fluorescent light bulb
c. the tape is too shiny
d. positioned too close to the shaft
Ans. B
Under normal condition storage batteries used for
815. starting emergency
diesel generator are maintained in a charged state
by which of the following methods?
a. trickle charging
b. fast charging
c. equalizing charge
d. full charging
Ans. A
The number of cycles per second occurring in an
816. AC voltage is known as the ____.
a. phase angle
b. frequency
c. wave form
d. half mode
Ans. B
When the electrolyte level of lead-acid storage
817. battery has decreased due to
normal evaporation, the level should be reestablished by adding
a. distilled water only
b. sulfuric acid only
c. a weak solution of distilled water and
sulfuric acid
d. a strong solution of distilled water and
sulfuric acid
263
Ans. A
Which of the listed classes of electrical insulation
818. are suited for the highest
operating temperature?
a. class O
b. class A
c. class B
d. class H
Ans. D
The armature cores of DC motors are constructed
819. with laminators to _________.
a. eliminate hysteresis
b. minimize brush sparking
c. reduce eddy current loses
d. compensate for armature reaction
Ans. C
When paralleling two AC alternators using
820. synchronizing lamp only, both lamps
will go dark when the alternators are
__________.
a. running at the same speed
b. grounded
c. of same polarity
d. in phase
Ans. D
A lead-acid battery cell sustaining short circuit
821. _______________.
a. will have unusually high voltage
b. will be indicated by lime accumulation on the
264
terminal posts
c. have excessively high temperature while
being charged
d. cannot complete full charging
Ans. C
Which of the instrument listed below is used for
822. checking insulation?
a. magnetometer
b. megohmmeter
c. dynamometer
d. ammeter
Ans. B
Equalization of the power factors of two
823. alternators operating in parallel
is accomplished _____________.
a. manually, by adjusting the governor control
b. automatically, by automatic voltage
regulators
c. manually, adjusting the output of current
transformer
d. automatically, by the designed action of the
governors
Ans. B
The field strength of a ship’s service DC generator
824. is adjusted by varying the ____.
a. speed of the generator
b. no. of field poles on the line
c. power factor of the field
d. resistance in the field
Ans. D
265
To parallel two generators, you should start the
825. prime mover _____________.
a. close the circuit breaker, adjust the voltage
then balance the loads
b. close the circuit breaker, adjust the bus
voltage then balance the loads
c. close the circuit breaker and the equalizer
switch then balance the loads
d. adjust the voltage, close the circuit breaker
then balance the loads
Ans. D
A lead acid battery can deliver 20 amperes
826. continuously for 10 hours with
an ampere-hour rating of _____________.
a. 20
b. 40
c. 200
d. 400
Ans. C
Which of the following statements, concerning the
827. general maintenance of a
brushless generator is correct?
a. paint should be applied to insulating surfaces
on an annual basis
b. alcohol should be used to remove dust and
grime from the windings
c. high pressure air should be used to blow out
carbon dust
d. accessible generator parts should be wiped
with a clean dry rag on
a periodic basis
266
Ans. D
The inductance of a coil is measured in
828. _____________.
a. ohms
b. volts
c. henries
d. amperes
Ans. C
The resistance of a conductor varies
829. _____________.
a. directly as its length and inversely as its cross
sectional area
b. inversely as its length and directly as its cross
sectional area
c. directly as its length and directly its cross
sectional area
d. inversely as its length and inversely as its
cross sectional area
Ans. A
The Wheatstone bridge is a precision measuring
830. instrument utilizing the
principle of changes in _____________.
a. inductance
b. capacitance
c. resistance
d. amperage
Ans. C
Which of the following should be the FIRST step
831. in removing a generator from
parallel operation?
267
a. trip the generator off the switchboard
b. turn off the electrical equipment
c. remove the load from the off-going
generator
d. increase the cycle of the generator staying on
the line
Ans. C
To limit the current flow through a DC voltmeter to
832. as low as possible, the moving
cool circuit is provided with a/an __________.
a. high series resistance
b. high parallel resistance
c. average voltage
d. peak voltage only
Ans. A
Most AC voltmeters are calibrated to indicate
833. _____________.
a. peak-to-peak voltage
b. root mean square voltage
c. average voltage
d. peak voltage only
Ans. B
Which of the ff conditions indicates a short834. circuited capacitor when ducking
condition with an ohmmeter?
a. the capacitor shows changing but the final
resistance reading is
appreciably less than normal
b. the reading is practically zero and remains
there
268
c. the capacitor shows no changing action, but
indicates a very high resistance
d. the pointer moves quickly to the low
resistance side of the scale, then slowly
recedes towards infinity
Ans. B
Hand portable phase sequence indicators are
835. useful when _____________.
a. preparing to parallel alternator
b. connecting lighting branch circuits
c. trouble-shooting DC motors
d. correcting shore power lines to the ship
Ans. D
The capacity of storage battery is measured in
836. _____________.
a. amp-hour capacity
b. volts
c. farads
d. amps
Ans. A
You are paralleling two alternators. The
837. synchronizing lamps grow dim and are totally
darkened as the synchroscope pointer
approaches the "0" position.
This indicates that the _____________.
a. alternator voltage are 180 degrees apart
b. circuit breaker can be closed
c. incoming alternator is running too slowly
d. synchroscope is defective or broken
Ans. B
269
When mixing electrolyte for a lead-acid battery
838. _____________.
a. stirring should always be avoided
b. a lead container should always be used
c. always pour the water into the acid
d. always pour the acid into the water
Ans. D
Which of the listed forms of water should be
839. added to a lead-acid battery?
a. saltwater
b. brackish water
c. distilled water
d. light water
Ans. C
Which of the problems listed below will occur with
840. a lead-acid battery is allowed to
remain in a discharged position for a long period
of time?
a. the battery may not be able to accept a full
charge
b. the electrolyte will turn sour
c. the corticosteroid sulfuric acid will attack the
plates
d. the separators will harden
Ans. A
When you check the specific gravity of the battery
841. electrolyte with a hydrometer,
it should be kept in mind that _____________.
a. the battery is fully charged when the indicator
270
floats low in the electrolyte
b. any water that has been previously added to
the cells will dilute the solution
and give false reading
c. a hydrometer reading is inaccurate if taken
immediately after
water is added to the cell
d. temperature has an effect on hydrometer
readings
Ans. C
A reverse current relay will prevent AC generator
842. motorization by _____________.
a. automatically redirecting the load
b. automatically speeding up the prime mover
c. tripping the panel board main switch
d. tripping the generator circuit breaker
Ans. D
One of the generator or motor bearings is
843. generally insulated from the end
housing in order to prevent _____________.
a. rapid brush wear
b. current leakage from shaft
c. excessive field winding heat
d. circulation of shaft currents induced in the
machine frame
Ans. D
An increase in the mount of current flow through
844. the armature of a shunt motor is
the final result of a/an _____________.
a. increase in the load on the motor
b. decrease in the load on the motor
271
c. increase in counter EMF
d. decrease in armature torque
Ans. A
A motor enclosure which protects against falling
845. liquids is classified as _________.
a. waterproof
b. drip proof
c. spray tight
d. moisture free
Ans. B
Insufficient brush pressure on a DC motor may
846. cause _____________.
a. generator overload
b. excess residual magnetism
c. water vapor absorption
d. sparking of the brushes
Ans. D
The type of motor control circuit that fails to pick
847. up when the coil voltage is
applied to the contractor coil, the cause may be
_____________.
a. low voltage protection
b. low voltage release
c. overload lock-out
d. reduced voltage starter
Ans. A
If magnetic controller contactor fails to pick up
848. when the coil voltage is applied
to the contactor coil, the cause may be
272
_________.
a. overload
b. misalignment of contacts
c. low spring pressure
d. an open contactor coil
Ans. D
The use of four diodes, in a full-wave bridge
849. rectifier circuit, will _____________.
a. provide unidirectional current on load
b. allow high leakage current on load
c. convert DC to AC
d. all of these choices
Ans. A
Motor controllers are seldom troubled with
850. grounds because _____________.
a. the auxiliary contact have high resistance
connection
b. the contractors and relays are mounted in a
non-conducting panel
c. the resistor banks are ground-proof
d. separate switches are available
Ans. B
A constant out voltage from an AC generator is
851. maintained by the _____________.
a. prime mover
b. voltage regulator
c. exciter generator
d. reverse power relay
Ans. B
273
Power transformers are rated in
852. _____________.
a. kilowatts
b. ampere turns
c. kilowatt-volts
d. kilovolt-amperes
Ans. D
An insulation test is performed on an electrical
853. equipment. Besides resistance
reading, what should be entered in the electrical
log?
a. maximum allowable temperature
b. temperature of machine at the time the
reading is taken
c. the normal temperature rise of the machine
d. none of these choices
Ans. B
A voltage relay with the addition of an air bleed, or
854. a dashpot to delay the action
of its contacts, is often used for ___________.
a. sequence control
b. acceleration control
c. low voltage release
d. all of these choices
Ans. D
Which of the solid AWG wire size has the smallest
855. physical cross-sectional area __.
a. 12
b. 14
c. 16
274
d. 18
Ans. D
An adjustable resistor, whose resistance can be
856. changed without opening the
circuit in which it is connected is called a/an
__________.
a. bleeder resistor
b. rheostat
c. transistor
d. bridge
Ans. B
The function of a stepdown transformer is to
857. reduce the load _____________.
a. voltage and current
b. voltage and increase line current
c. current and increase line voltage
d. power
Ans. B
A loud buzzing noise in an AC controller is
858. probably caused by _____________.
a. poor contact with the overload relay
b. an incorrect sized heater
c. a broken shading coil
d. abnormal starting current
Ans. C
Increasing the load to the secondary windings of a
859. transformer will cause a/an ____.
a. decrease in primary voltage
b. increase in primary voltage
275
c. decrease in primary current
d. increase in primary current
Ans. D
What is the function of the voltage regulators used
860. with AC generators ?
a. to cut out generators when they are no
longer
b. to cut an additional generator automatically
as required
c. to divide the KW load between the two
generators
d. to divide reactive current between generators
operating in parallel
Ans. D
The basic operation principle of a transformer is
861. attributed to _____________.
a. electromagnetic induction
b. variance of a conductor in a magnetic field
c. mutual reaction
d. thermal transmission
Ans. A
Which of the meters listed should be used after a
862. circuit has been electronically
disconnected ?
a. wattmeter
b. frequency meter
c. ammeter
d. ohmmeter
Ans. D
276
The output voltage of a 440V, 60Hz AC generator
863. is controlled by the _________.
a. load on the alternator
b. load on the prime mover
c. speed of the prime mover
d. exciter output voltage
Ans. C
When a transformer is used to step down voltage,
864. the low voltage winding is _____.
a. part of core
b. the primary coil
c. the secondary coil
d. not insulated
Ans. C
The cycle per second developed by an alternator
865. aboard your vessel is
determined by _____________.
a. The speed of the prime mover
b. The resistance applied to the field rheostat
c. The output of voltage regulator
d. The output of excitation
Ans. A
Magnetic chatter on “pumping" occurring in a
866. magnetic contactor can be
caused by _____________.
a. dirt or grease in contact surfaces
b. mechanical interference in the contacts
c. chattering contacts on the relay
d. magnetic lockout of the relay
277
Ans. C
Relative to the secondary winding of a step-up
867. transformer, the primary
winding will have _____________.
a. more turns
b. fewer turns
c. half as many turns
d. twice as many turns
Ans. B
To equalize the power factor of two alternators
868. operating in parallel, the _________.
a. field excitation of both units is adjusted
b. governor of both units are adjusted
c. kilowatt load is evenly divided
d. phase sequence is altered
Ans. A
When trouble shooting motor controllers, a
869. shorted relay or contractor coil is
often indicated by _____________.
a. a resistance reading of infinity or an
ohmmeter
b. charred insulation and/or blown control fuse
c. a reading of zero on a megger
d. a higher than normal voltage reading
Ans. B
You can determine if a circuit breaker is tripped by
870. _____________.
a. examining the position of the handle
b. checking for the warm breaker
278
c. looking for a burnt out link
d. looking for the tripped breaker light
Ans. A
During maintenance of circuit breakers
871. _____________.
a. always smooth roughened contact surfaces
with a file
b. never pass more than rated breaker current
through the loaded element
c. inspect for wear and misalignment of main
contacts
d. assume heater elements installed are of
correct size
Ans. C
Accidental grounds is a shipboard electrical
872. system must be repaired as
soon as possible as they will _________.
a. result in immediate power outages
b. damage circuit breakers
c. appear on the ground detection system
d. damage insulation and may cause outages
Ans. D
Which of the following statement is TRUE
873. concerning transformer operation?
a. the inductance in the primary side is the same
as the secondary side
b. voltage is the same of primary side and the
secondary side
c. current is the same of primary side and the
secondary side
d. power to the primary side is higher than the
279
power in the secondary side
Ans. D
A lamp has a source voltage of 110 volts and a
874. current of 0.9 amps.
What is the resistance of the lamp?
a. 0.008 ohm
b. 0.08 ohm
c. 12.22 ohm
d. 122.22 ohm
Ans. D
A voltage regulator installed in a direct current
875. generator serves the purpose of ___.
a. varying the shunt field resistance
b. adjusting the cross current
c. lowering the armature circuit resistance
d. limiting the compensating field resistance
Ans. A
Electric motors intended for use outside the
876. engine room are frequently rated to
run at a designed ambient temperature of 40
degrees centigrade. What is the
equivalent temperature in degrees fahrenheit?
a. 54.2 degrees Fahrenheit
b. 72 degrees Fahrenheit
c. 104 degrees Fahrenheit
d. 129.6 degrees Fahrenheit
Ans. C
A direct current passing through a wire wrapped
877. around a soft iron is a good
280
example of a simple ___________.
a. magnetic shield
b. electromagnet
c. transformer
d. armature
Ans. B
Which of the substances mentioned below can be
878. used to shield sensitive
equipment from static magnetic fields?
a. permeable iron
b. glass
c. varnished cloth0
d. bakelite
Ans. A
The timer element found in a reverse-power relay
879. obtains the operating
torque via _____________.
a. line voltage
b. the main bus
c. electromagnets
d. a separate battery source
Ans. C
Coast Guard Regulation 46 CFR require each
880. switchboard to have ____________.
a. non-conductive deck covering at the front
b. non conductive deck covering at the rear
c. a nameplate for each circuit breaker
d. all of these choices
Ans. D
281
Emergency lightings aboardship should be a/an
881. ______________.
a. illuminated at all times while vessel is
underway
b. illuminated automatically and actuated upon
failure of the main
lighting system
c. portable battery operated and have sufficient
capacity
d. all of these choices
Ans. B
As per Coast Guard Regulations 46 CFR,
882. emergency generator set aboard
ocean-going vessels must be capable of supplying
emergency lightings for
a minimum period of ______________.
a. 18 hours
b. 36 hours
c. 24 hours
d. 6 hours
Ans. A
As per Coast Guard Regulations 46 CFR,
883. emergency generator fuel tank full
capacity must be capable of supplying the unit for
a period of _____________.
a. 6 hours
b. 18 hours
c. 24 hours
d. 36 hours
Ans. B
884. As per Coast Guard Regulation 46 CFR, which of
282
the below listed items is the
only permissible starting aid for the emergency
diesel generator engine?
a. ether
b. lube oil heater
c. jacket water heater
d. fuel oil heater
Ans. C
The source of emergency lighting and power loss
885. of normal ship's power on a
cargo vessel should be obtained from the
______________.
a. emergency generator supply to the emergency
switchboard
b. emergency generator supply to the main
switchboard
c. battery supply to the main switchboard
d. turbogenerator supply to the emergency
switchboard
Ans. A
An electrical device which employs a stationary
886. armature and a rotating
magnetic field is used aboardship as a
___________.
a. magnetic amplifier
b. ship service generator
c. DC generator
d. saturable core reactor
Ans. B
According to USCG Regulations 46 CFR, how
887. often shall internal combustion
283
engine driven emergency generators be operated
under load?
a. once a week for 2 hours
b. once a month for 2 hours
c. every six (6) months for 4 hours
d. once a week for 4 hours
Ans. B
The emergency switchboard 24v DC supply is
888. used to provide power to the ______.
a. general alarm system
b. gyrocompass power supply system
c. smoke detection system
d. all of these choices
Ans. D
284