| 1. | DC shunt relays are made of ? | |
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many turns of thick wire
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few turns of thin wire
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turns of thick wire
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many turns of thin wire
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Report Question| 2. | Fault diverters are basically ? | |
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circuit breakers
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relays
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fuses
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fast switches
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| 3. | A thermal protection switch can protect against ? | |
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over voltage
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overload
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temperature
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short-circuit
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| 4. | The voltage appearing across the contacts after opening of the circuit breaker is called ...... voltage ? | |
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arc
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recovery
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operating
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surge
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| 5. | In a circuit breaker the basic problem is to ? | |
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emit the ionizing electrons
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transmit large power
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extinguish the arc
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maintain the arc
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| 6. | The time of closing the cycle, in modern circuit breakers is ? | |
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0.10 sec
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0.003 sec
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0.01 sec
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0.001 sec
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| 7. | Which of the following is the least expensive protection for over current is low voltage system ? | |
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Air break circuit breaker
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Oil circuit breaker
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Rewire able fuse
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Isolator
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| 8. | The reflection co-efficient at the open circuited end of a transmission line ? | |
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unity
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zero
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infinity
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none of the above
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| 9. | Distance relays are generally ? | |
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impedance relays
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split-phase relays
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reactance relays
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none of the above
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| 10. | Series reactors should have ? | |
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high impedance
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high resistance
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low resistance
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low impedance
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