Exam 5: Electrical Protection and Safety: Part B

Distance protection scheme is preferred over graded lime-lag over-current protection in HV and EHV lines because

Tap changing transformers are employed for

In a isolated neutral system, when a single line to ground fault occurs

In carrier current protection the purpose of the wave trap is for

Which is the pilotless protection method for feeder line ?

Time graded protection of a radial feeder can be achieved by using

Field failure in an alternator occurs due to

Requirements of protection power station buildings against direct strokes are

The bias factor S in unit protection synchronous generators

For the protection of a large squirrel cage induction motor against single phase normally

In between the generating station and consumers a number of transformation and switching stations exist, these are called the

With large reactance interconnector between two power stations

The types of faults that occur in electric motors are

The protection against direct lighting strokes and a high-voltage steep waves is provided by

The main function of under voltage protective device generally employed with a motor starter is to

For the protection of transformers, harmonic restraint is used to guard against

The most commonly used method for the protection of three phase feeder is

As soon as a fault develops in a generator stator, it is essential to suppress field excitation, otherwise

In a balanced voltage pilot wire protection scheme if the pilot circuit gets opened, the relay will

The frequency of carrier transmitted by microwave pilot is in the range of