7) A 480 volts distribution system delivers a load of 120kw 0.707 pf lagging, what value of the capacitor to be connected across the load so that the power factor is acceptable to Phil Distribution Code?

1. A Zone 2 fault is detected in 25 cycles of a 60 Hz power system and the circuit breaker clears in 5 cycles. Calculate the fault clearing time for this case. a) 60 ms b) 500 ms c) 120 ms d) 150 ms 2. The Burden on a CT should always be kept a) High b) Low c) Either, because burden does not affect the CT d) At the rated burden value for the CT 3. The purpose of backup protection is a) To increase speed b) To leave no blind spots c) To guard against failure of primary d) To increase reach 4. In distance protection scheme, which Zone is set to trip instantaneous without any delay? a) Zone 3 b) Zone 2 c) Zone 1 d) All of the above 5. The protective relay is provided to: 1) Provide additional safety by limiting arcing current during circuit breaker operation. 2) Close the contacts when the actuating quantity attains a certain predetermined value. a) Only 1 b) Only 2 c) Both 1 and 2 d) None of these

72. In 132 kV system, the phase to ground ca- pacitance is 0.01 µF and inductance is 6H. The voltage that appears across the contacts of circuit breaker if a magnetising current of 10A is interrupted is (ii) 356 kV (iv) 176 kV (1) 156 kV (iii) 245 kV