DieselShip's Online Content Library

Q1. a) Draw a circuit diagram of a transistor connected as a common emitter amplifier including Blas resistors, coupling and decoupling capacitors. (8)

b) Explain the operation of the circuit components (8)

Q2. With the aid of a block diagram, briefly describe the effect that negative voltage feedback has on an amplifier and state the advantages resulting from the use of negative feedback. (16)

Q3. a) Sketch a main engine shaft driven generator arrangement with an electronic system for frequency correction. (8)

b) Describe the operation of the generator arrangement sketched in (a). (8)

Q4.a) List the factors that determine the starting torque of the three-phase induction motor. How does this torque generally compare with the value of the rated torque (6)

b) An 18.65 KW, 6 Pole, 50 Hz, 3 phase 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 three-phase winding. (10)

Q5.a) With the aid of delta and star connection diagrams, state the basic equation from which the delta -star and star- delta conversion equation can be derived (6)

b) A 230/115 V, single phase transformer is supplied with a load of 5A at p.f. 0.86 lagging. The no-load current is 0.2 A at p.f. 0.208 lagging. Calculate the primary current and p.f. (10)

Q6. A 3000 KVA, 6-pole 3 phase, star connected alternator runs at 1000 r.p.m. in parallel with other machines on 3300V bus-bars. The synchronous reactance is 25%. Calculate the synchronizing power for one mechanical degree of displacement and the corresponding synchronizing torque. (16)

Q7. Describe the pumping of machinery space bilges and disposal of oil/sludge residues of your ship using the following guidelines:

a) When outside the twelve mile limit and not in a special area: (4)

b) Inside the twelve mile limit and in special areas (4)

c) For logging the discharges; (4)

d) The disposal of oily residues for vessels with no incinerator (4)

Q8. With references to the pump room of an oil tanker describe the following with particular emphasis on safety aspects:

a) Ventilation system (5)

b) Procedure to be followed for pump room entry. (6)

c) Lighting system. (5)

Q9. With reference to “ISM Code” write short notes on:

a) Objectives of the ISM code (4)

b) Resource and personnel (4)

c) Masters Authority and responsibility (4)

d) Functional requirements for a safety management system. (4)