DieselShip's Online Content Library

Q2. a) Briefly explain the principle of Operation of induction Motors (4)

b) What is slip for an induction motor? (4)

c) Draw a simple ladder logic diagram of star delta starting of an induction motor. (8)

Q3. With reference to batteries onboard:

a) Distinguish between ‘Lead acid cell’ and ‘Alkaline cell’ (6)

b) Describe how a battery of alkaline cells may be tested for its usefulness, after a long storage and if found deficient, how it can be remedied? (6)

c) Explain how the ambient temperature is taken into account when determining the condition of the battery (4)

Q1. What is Zener diode and how does it regulate the voltage? What happens to the series current, load current and Zener current when the d.c input voltage of a Zener regulator increases? Draw a neat diagram of Zener regulator and explain. (16)

Q3. With Respect to Insulated and Earthed Neutral Systems used on board:

a) Discuss the Advantages and Disadvantages of both Insulated and Earthed Systems used on board. (8)

b) What is earth fault and how do you identify Earth fault in the 440 V system onboard. (4)

c) Discuss the consequences of earth fault in an earthed distribution system. (4)

Q5. With Reference to different types of transformers used onboard.

a) Discuss the basic principle of operation of a transformer (5)

b) Enumerate the different types of transformers used onboard also state their functions for which they are used. (5)

c) A 440/110 V single phase transformer supplies a load of 5kW at 0.8 power factor load. Calculate the primary and secondary currents. (Ignoring transformer power losses)? (6)

Q6. A 100 KVA, 2400/240 V, 50 Hz, 1-phase transformer has no- load current of 0.64 A and a core loss of 700 W, when its high voltage side is energized at rated voltage and frequency . calculate the two components of no-load current. If this transformer supplies a load current of 40 amp at 0.8 lagging power factor at its low voltage side, determine the primary current and its power factor. Ignore leakage impedance drop. (16)

Q7. How will you fight a fire in a galley? How will you at least restrict the fire if you are the first person to sight the fire in the galley? (16)

Q9. With reference to MARPOL Annex IV
a) Draw a biological sewage treatment plant and explain the principle of operation. (8)
b) Periodical maintenance and checks and tests required to be done to verify the effectiveness of the above system. (8)

Q9. With respect to the hazardous areas of tankers.
(a) Explain the term flameproof (Ex d) for electrical equipment. (6)
(b) State the type of electrical equipment that would be protected in this way. (5)
(c) List likely defects of flameproof equipment. (5)