ACES EE System - Line Protection

A relay in which the measurement is performed by a stationary circuit and which has no moving parts is called

• static relay

• different relay

• time relay

• instantaneous relay

For high voltage ac circuit breakers, the rated short circuit current is passed for ___ seconds

• 0.1

• 20

• 3

• 30

Which of the following is not a type contractor for circuit breakers?

• vacuum

• pneumatic

• electro-pneumatic

• electro-magnetic

Interrupting medium in a contactor for circuit breakers may be

• air

• SF₆ gas

• oil

• any of these

Which of the following circuit breakers has the lowest voltage range

• air blast

• SF₆

• air break

• tank type oil

Which of the following materials is not used in extinguishing the arc in case of a circuit breaker?

• water

• air

• vacuum

• SF₆

The transient voltage that appears across the contacts of a circuit breaker at the instant of arc extinction is called

• restriking voltage

• recovery voltage

• supply voltage

• peak voltage

A relay used for protection of motors against overload is

• thermal relay

• impedance relay

• Buchholz relay

• magnetic relay

The number of cycles in which a high speed circuit breaker can complete its operation is

• 3 to 8

• 20 to 30

• 10 to 18

• 40 to 50

A material best suited for manufacturing of fuse wire is

• silver

• copper

• lead

• aluminum