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95MET-4
Sr. No. 5
EXAMINATION OF MARINE ENGINEER OFFICER
Function: Electrical, Electronic & Control Engineering at Operational Level
MARINE ELECTROTECHNOLOGY
India (2003)
M.E.O. Class IV
(Time allowed - 3hours)
Morning Paper
Total Marks 100
NB : (1)Answer SIX Questions :
SECTION -1 :- Answer atleast TWO Questions
SECTION -2 :- Answer atleast TWO Questions
(2)All Questions carry equal marks
(3)Neatness in handwriting and clarity in expression carries weightage
(4) Illustration of an Answer with clear sketches / diagrams carries weightage.
SECTION - 1
1.
Explain the term single phasing as applied to poly phase induction motors.
(a) State the likely causes of single phasing and the consequences if motors are not adequately
protected.
(b) Describe with the aid of sketches THREE methods for motor protection should single phasing
occur.
2.
(a) Sketch a emergency standby battery charging-discharging circuit of the four pole switch type
which allows one section of the battery to be on charge while the other section is available for
discharge, including the arrangement for quick charge and trickle charge.
(b) State why ONE of the following battery types requires a trickle charge and the other does not:
i) lead acid
ii) lkaline nickel cadmium.
3.
With the aid of clearly drawn and labeled sketches, describe the construction and the principle of
operation, of a galvanometer of permanent-magnet moving-coil type. Is such an instrument suitable
for use in A.C. circuits? Give reasons for your answer.
4.
With reference to oil monitoring of bilge and tanker ballast discharges:
(a) Describe with the aid of a sketch, the general arrangement of an oil monitoring
system;
(b) State the inputs that are recorded;
(c) Explain the difficulties encountered with the efficient operation of the oil
monitoring system.
5.
The function of a rectifier is similar to that of a _______.
(a) trap
(b) regulating valve
(c) check valve
(d) filter
SECTION - 2
6. A small 2-pole magneto has a useful flux of 0.0015 webers. Calculate the average induced e.m.f. for
an armature having 400 turns driven at 1,200 r.p.m.
7. A shunt motor has an armature resistance of 0.2 ohms and with an armature current of 120 amperes
runs at 750 r.p.m. off a 400-volt supply. Calculate the speed and armature current of the motor if the flux
per pole is reduced to 75 per cent of its initial value, the total torque remaining unaltered.
8. a) Explain about early effect or base width modulation.
b) Sketch I/P and O/P characteristics of CE configuration for a given transistor.
c) Relate  and , where  = large signal current gain,  = (hFE)d.c. of BJT.
9. Calculate the resistance of a shunt required to operate with a mill ammeter, Which gives full-scale
deflection for a current of 15mA and which has a resistance of 5 Ohms.(Note. 5 Ohms can be taken to
include the resistance of the connecting leads, since no specific mention of lead resistance has been
made). The combination of meter and shunt is required to read currents up to 100A.
10. An alternating voltage, in the form of a sine wave, having a peak value of 340V, is applied to the
ends of a 24 resistor. Calculate the r.m.s. value of the current in the resistor.
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95MET-4
Sr. No. 5
EXAMINATION OF MARINE ENGINEER OFFICER
Function: Electrical, Electronic & Control Engineering at Operational Level
MARINE ELECTROTECHNOLOGY
M.E.O. Class IV
(Time allowed - 3hours)
Morning Paper
India (2003)
NB : (1)Answer SIX Questions :
SECTION -1 :- Answer atleast TWO Questions
SECTION -2 :- Answer atleast TWO Questions
(2)All Questions carry equal marks
(3)Neatness in handwriting and clarity in expression carries weightage
(4) Illustration of an Answer with clear sketches / diagrams carries weightage.
Answers
SECTION - 1
Question 5 :
Correct
Answer
:C
Total Marks 100