Air blast circuit breakers for 400 kV power system are designed to operate in (a) 100 microsecond (b) 50 millisecond (c) 0.5 sec (d) 0.1 sec

Air blast circuit breakers for 400 kV power system are designed to operate in (a) 100 microsecond (b) 50 millisecond (c) 0.5 sec (d) 0.1 sec
by

1 Answer

Answer :

(b) 50 millisecond
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Related questions

Air blast circuit breakers for 400 kV power system are designed to operate in?

Last Answer : Air blast circuit breakers for 400 kV power system are designed to operate in 50 millisecond.

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Magnetic circuit breaker has ______ trip action. (a) delayed (b) instantaneous (c) both of the above (d) none of the above

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With which of the following, a circuit breaker must be equipped for remote operation ? (a) Inverse time trip (b) Time-delay trip (c) Shunt trip (d) None of the above (e) All of the above

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The arcing contacts in a circuit breaker are made of (a) copper tungsten alloy (b) porcelain (c) electrolytic copper (d) aluminium alloy

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The main function of a fuse is to (a) protect the line (b) open the circuit (c) protect the appliance (d) prevent excessive currents (e) none of the above

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Overhead system can be designed for operation up to (a) 11 kV (b) 33 kV (c) 66 kV (d) 400 kV

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Last Answer : (c) 66 kV

Overhead system can be designed for operation up to (a) 11 kV (b) 33 kV (c) 66 kV (d) 400 kV

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Last Answer : (c) 66 kV

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The relay operating speed depends upon (a) the spring tension (b) the rate of flux built up (c) armature core air gap (d) all of the above

Description : The relay operating speed depends upon (a) the spring tension (b) the rate of flux built up (c) armature core air gap (d) all of the above

Last Answer : (d) all of the above

SF6 gas (a) is yellow in colour (b) is lighter than air (c) is nontoxic (d) has pungent small (e) none of the above

Description : SF6 gas (a) is yellow in colour (b) is lighter than air (c) is nontoxic (d) has pungent small (e) none of the above

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Overfluxing protection is recommended for (a) distribution transformer (b) generator transformer of the power plant (c) auto-transformer of the power plant (d) station transformer of the power plant

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For the protection of power station buildings against direct strokes the requirements are (a) interception (b) interception and conduction (c) interception, conduction and dissipation (d) interception, conduction, dissipation and reflection (e) none of the above

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Last Answer : (c) interception, conduction and dissipation