EE8602 PSG Unit 2 Quiz

An impedance relay is used for

• Earth faults

• Interphase faults

• Both (a) and (b)

• None of these

Relay gets its operating energy from

• Transformer

• Alternator

• Overhead lines

• C.T., P.T.

Good relay should possess

• Speed & reliability

• Aped & sensitivity

• Adequateness & selectivity

• All of these

Earthing transformer is used to

• Improve neutral wire’s current capacity

• Avoid overheating of transformer

• Provide artificial earthing

• Avoid harmonics

Percentage differential protection is used to prevent against

• Inter-turn faults

• Heavy Loads

• External Faults

• Magnetizing current

Back up protection is needed for

• Over voltage

• Short circuits

• Over current

• All of these

An instantaneous relay is

• Permanent moving magnet

• Induction cup

• Shaded pole

• Moving coil

Relays for transmission line protection are

• In three zones

• In two zones

• Independent of zone

• None of these

Induction cup relays responds to

• Current

• Power

• Voltage

• Impedance

Split-phase relay responds to

• Over load faults

• Over voltage

• Inter turn faults

• All of these