DieselShip's Online Content Library

Q1. With reference to alkaline batteries used on board ship.

a) Describe the operation of a battery cell and state the material used. (8)

b) Describe how the cells are mounted to form a battery. (4)

c) State the advantages and disadvantages compared with lead-acid batteries. (4)

Q2. With reference to a 3 speed a.c. cage motor driven cargo winch:

a) Sketch a circuit diagram for a pole change motor. (8)

b) Describe how speed change and braking are achieved. (8)

Q3. With reference to electronic control systems:
a) Draw a simple block diagram for temperature control (8)
b) Describe each component shown in the diagram in (a). (8)

Q4. a) Explain the preference for a 60 Hz system. Describe the dangers of running a 50 Hz system from a 60 Hz supply. (6)
b) A transistor amplifier stage comprises a transistor of parameters hie = 800  hfe = 5O and hoe = 20µ S, and bias components and coupling capacitors of negligible effect. The input signal consists of an e.m.f. of 60 mV from a source of internal resistance 2.2 k , and the total load on the stage output is 4 k . Determine the current, voltage and power gains of the amplifier stage. (10)

Q5. A) Explain how the efficiency and regulation of a transformer can be assessed by open circuit and short circuit tests? (6)
b) A tuned circuit consisting of a coil having an inductance of 200 mH and a resistance of 20 Ω in parallel with a variable capacitor is connected in series with a resistor of 8000 Ω across a 60V supply having a frequency of 1 MHz Calculate:
a) The value of C to give resonance.
b) The dynamic impedance and the Q factor of the tuned circuit.
c) The current in each branch. (10)

Q6. a) Explain distribution factor and pitch factor for alternator windings. (6)
b) An eight-pole armature is wound with 480 conductors. The magnetic flux and the speed are such that the average e.m.f. generated in each conductor is 2.2 V, and each conductor is capable of carrying a full load current of 100 A. Calculate the terminal voltage on no load, the output current on full load and the total power generated on full load when the armature is
a) lap-connected
b) wave-connected (10)

Q7. 'Fire Control Plan' is one of the requirements to be carried on board ship. State the International Convention under which the plan is made mandatory. With reference to this plan explain the following:
a) What all information are available in the plan. (8)
b) Which all locations it is stowed/exhibited and the reasons. (8)

Q8. With reference to "ISM Code" write short notes on
a) Management Review (5)
b) Advantage of drills and procedures (5)
c) Internal Audit (6)

Q7.  With reference to the Maritime Labour Convention (MLC) 2006. Discuss the requirements for seafarers regarding: -
a) Minimum age to work onboard vessels (5)
b) Seafarers Employment agreements (5)
c) Hours of work and hours of rest. (6)