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The relay with inverse time characteristic will operate within 5 to 10 sec.

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Answer : d

Description : A relay used for protection of motors against overload is :  (A) Impedance relay (B) Electromagnetic attraction type (C) Thermal relay (D) Buchholz's relay

Answer : A relay used for protection of motors against overload is : Thermal relay

Description : A relay has a rating of 5 A, 2.2 sec IDMT and a relay setting of 125% TMS = 0.6. It is connected to a supply circuit through a C.T. 400/5 ratio. The fault current is 4000 A. The operating current of the relay is

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Description : What is the difference between relay and contactor?

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Answer : A negative sequence relay is used for protection of Generator 

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Description : To prevent mal-operation of differentially connected relay while energizing a transformer, the relay restraining coil is based with  (1) second harmonic current  (2) third harmonic current  (3) fifth harmonic current  (4) seventh harmonic current

Answer : To prevent mal-operation of differentially connected relay while energizing a transformer, the relay restraining coil is based with  second harmonic current 

Description : Reactance relay is normally preferred for protection against

Answer : Reactance relay is normally preferred for protection against earth faults

Description : In the induction type directional over current relay, when a short-circuit occurs in the circuit (A) power flows in reverse direction (B) power flows in normal direction (C) directional power element does not operate (D) over current element is not energized

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Description : A solid state relay (A) withstands voltage transients (B) does not require auxiliary dc supply (C) provide low burden on CT and P (D) does not provide earth fault protection

Answer : A solid state relay provide low burden on CT and P

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Answer : With fault clearing time, the transient stability of a power system decreases

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Answer : If a relay fails to operate for a fault within its reach, it is said to Under reach

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Description : what is reverse power relay?

Answer : Thereverse powerrelay is a directional protective relay that prevents power from flowing in the reverse direction. Read our article going back ... it all to be up to date. And if you do, read it anyway just to check if youreallydo!

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