Exam 1: Electrical Protection and Circuit Breakers

With which of the following, a circuit breaker must be equipped for remote operation ?

The arcing contacts in a circuit breaker are made of

Large internal faults are protected by

SF6 gas

In order that current should flow without causing excessive heating or voltage drop, the relay contacts should

Directional relays are based on flow of

D.C. shunt relays are made of

The main function of a fuse is to

The current zero interruption, in oil and air blast circuit breakers, is achieved by

Air blast circuit breaker is used for

Circuit breakers are essentially

Fault diverters are basically

The relay operating speed depends upon

Circuit breakers usually operate under

Thermal circuit breaker has

Which of the following medium is employed for extinction of arc in air circuit breaker ?

Magnetic circuit breaker has ______ trip action.

A transmission line is protected by

Thermal overload relays are used to protect the motor against over current due to

A thermal protection switch can protect against