DieselShip's Online Content Library

Q2. State the application of the synchronous motors. Discuss how a synchronous motor can function as a synchronous capacitor. Compare synchronous motors with induction motor drives (16)

Q1. Sketch and describe a main engine shaft driven generator arrangement with an electronic system for frequency correction. (16)

Q6. With Reference to 3-phase Transformers:

a) Discuss the essential and desirable conditions to be fulfil for operating two three-phase transformers in parallel. (5)

b) What are the advantages of transformer bank of three 1-phase transformers over a unit three phase transformer of the same kVA rating? (5)

c) In a 25 kW, 3300/233V, 1-phase transformer the iron and full load copper losses are 350 watts and 400 watts respectively. Calculate the efficiency at half load 0.8 P. F (6)

Q4. With respect to Alternators onboard:

a) Briefly explain true power, Apparent power and power factor? (8)

b) The alternator is rated for 750 KVA at 0.85 PF, what is the maximum load (Kilo Watt) that can be put on it? Would you be overloading the alternator if the kilowatt reading were now 620 KW and the power factor 0.80? (8)

Q9. Briefly discuss the following with respect to safety of navigation:

a) Bridge Navigation Watchkeeping Alarm System (BNWAS) (6)

b) Long Range Identification and Tracking of ships (LRIT). (5)

c) Voyage Simplified Voyage Recorder (VDR/S-VDR) (5)

Q7. With Reference to Electrical Safety onboard a vessel:

a) Write Short note on “Electric Shock” (6)

b) Enumerate the relation between Shock Current Levels, the Applied Voltage and the Body resistance. (5)

c) How do you treat a person who has suffered an electric shock onboard from a AC supply? (5)

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)