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Q2. a) Describe the circuit breaker for an A.C. generator using a sketch to show how arcing is controlled. (8)

b) Explain the sequence of events that might occur if the breaker opens on a short circuit and state the check you would require following such event. (4)

c) Give a safe procedure to follow should a main circuit breaker fail to open under fault Condition. (4)

Q2. In a ship’s power system, the neutral on the low voltage side is not grounded, but it is mandatory to ground the neutral in high voltage systems. Discuss in detail for the above difference and with suitable sketches, explain the different earthing arrangements for HV system (16)

Q2. a) In A.C. generators, voltage dip occurs in two stages.

i) Sketch a voltages-time graph showing the pattern of voltage dip. (4)

ii) Referring to this graph, state the reasons the effect on the electrical system of a small power installation when a large load is suddenly switched on. (4)

b) Explain EACH of the following categories of voltage control:

i) Error operated (4)

ii) Functional (4)