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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)