SWITCH GEAR QUIZ

The power loss is an important factor for the design of

motor

transmission line

generator

feeder

TRUE ANSWER : ?
YOUR ANSWER : ?

The making capacity of a circuit breaker is equal to

None of these

√2 × symmetrical breaking capacity

√3 × symmetrical breaking capacity

2.55 × symmetrical breaking capacity

TRUE ANSWER : ?
YOUR ANSWER : ?

Arc in a circuit breaker is interrupted at

maximum current

minimum voltage

maximum voltage

zero current

TRUE ANSWER : ?
YOUR ANSWER : ?

The reflection co-efficient at the open circuited end of a transmission line

None of these

unity

infinity

zero

TRUE ANSWER : ?
YOUR ANSWER : ?

An isolator is designed to open a circuit under

None of these

no load

normal conditions

full load

TRUE ANSWER : ?
YOUR ANSWER : ?

Arc in a circuit breaker behaves as

a capacitive reactance

an inductive reactance

a resistance increasing with voltage rise across the arc

a resistance decreasing with voltage rise across the arc

TRUE ANSWER : ?
YOUR ANSWER : ?

Circuit breakers usually operate under

steady state of short circuit current

after dc component has ceased

sub-transient state of short circuit current

transient state of short circuit current

TRUE ANSWER : ?
YOUR ANSWER : ?

The pick-up current of a relay is 7.5 A and the fault current in relay is 30 A. Its plug-setting multiplier (P.S.M.) is

4

2

8

6

TRUE ANSWER : ?
YOUR ANSWER : ?

Admittance relay is

None of these

directional relay

non-directional relay

impedance relay

TRUE ANSWER : ?
YOUR ANSWER : ?

If the length of the arc in a circuit breaker increases, its resistance

None of these

decreases

increases

remains same

TRUE ANSWER : ?
YOUR ANSWER : ?

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