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95MET-2
Sr. No. 1
EXAMINATION OF MARINE ENGINEER OFFICER
Function: Electrical, Electronic & Control Engineering at Management Level
MARINE ELECTROTECHNOLOGY
India (2004)
M.E.O. Class II
(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.
With reference to the provision of a shore electrical supply to a ship:
(a) Sketch an arrangement for taking A.C. shore supply;
(b) Describe the method of safely connecting the arrangement sketched in (a) to the shore supply.
2.
With reference to U.M.S. operation:
(a) State with reasons the essential requirements for unattended machinery spaces;
(b) As Chief Engineer, describe how you would respond to the irretrievable failure of the machinery
space fire alarm system whilst the ship is on voyage.
3.
Direct on line starting for large induction motors such as those for bow thrust units, may not be
viable.
(a) State the reasons for this.
(b) Sketch a starting system that may be used for such motors.
(c) Describe the starting method sketched in (a, b ).
4.
(a) In a.c. generators, voltage dip occurs in two stages.
(i) Sketch a voltage-time graph showing the pattern of voltage dip.
(ii) Referring to this graph, state with reasons the effect on the electrical system of a small
power installation when a large load is suddenly switched on.
(b) Explain EACH of the following categories of voltage control:
(i) Error operated;
(ii) Functional.
5.
Which of the following devices will prevent a DC generator from becoming motorized?
(a) Over current relay
(b) Motorization trip
(c) Reverse power relay
(d) Reverse current relay
Give a detailed explanations as to why the other options were not considered.
SECTION – 2
6.
Draw the circuits of resistive and capacitive voltage dividers. What are the differences between
them? For the following circuit, what is the voltage across C2.
VT = 120 V
f = 2 KHz
C1=2
F
C2=1
F
VC2
7.
Explain the working principle of a three phase induction motor. What are the various types of
rotors? An 18.65 kw, 6-pole, 50 Hz, 3- slip-ring induction motor runs at 960 rpm on full load
with a rotor current per phase of 35 A. Allowing 1 kw for mechanical losses, find the resistance /
phase of 3-phase rotor winding.
8.
The armature and field resistances of a 220V shunt motor are 0.25 and 110 ohms respectively and,
when running on no load, the motor takes 6A. Calculate the losses attributable to iron, friction and
windage and assumingthis value to remain constant on loads, determine the efficiency when the
current supplied is 62A
9.
A three-phase transformer has 560 turns on the primary and 42 turns on the secondry.The primary
windings are connected to a line voltage of 6.6kV.Calculate the secondary line voltage when the
transformer is connected (a) Star-Delta, (b) Delta-Star.
10.
Two shunt generators X and Y work in parallel. Their external characteristics may be assumed to
be linear over their normal working range. The terminal voltage of X falls from 265 V on no load
to 230 V when delivering 350 A to the bus bars, while the voltage of Y falls from 270 V on no
load to 240 V when delivering 400 A to the bus bars. Calculate the current which each machine
delivers when they share a common load of 500 A. What is the bus bar voltage under this
condition and the power delivered by each machine?
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95MET-2
Sr. No. 1
EXAMINATION OF MARINE ENGINEER OFFICER
Function: Electrical, Electronic & Control Engineering at Management Level
MARINE ELECTROTECHNOLOGY
M.E.O. Class II
(Time allowed - 3hours)
Morning Paper
India (2004)
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.
Q5.
Correct
Answer
:D
Total Marks 100