How do you test reverse power trip, high current trip, preferential trip?

How do you test reverse power trip, high current trip, preferential trip?
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1 Answer

Answer :

Reverse power trip – refer answer for question 11. Also ask E/O.
High current (over load trip) – Set your overload relay high current trip setting to say 75% of the rated current. Run the motor. The relay will trip the breaker. Another way of testing it is pushing the trip button on the relay which trips the breaker.
Preferential trip – With one generator running, try to switch on additional loads to overload the generator. Preferential trip will trip all the non-critical loads. Also ask E/O.
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Related questions

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Description : How do you test reverse power trip?

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The two conductors of a transmission line carry equal current I in opposite directions. The force on each conductor is (a) proportional to 7 (b) proportional to X (c) proportional to distance between the conductors (d) inversely proportional to I

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What is a current transformer and voltage transformer?*

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Does current flow through hull during welding?

Description : Does current flow through hull during welding?

Last Answer : Ask E/O. Yes I think

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Description : How does current flow during welding?

Last Answer : The current flows through the electrode and to the clamp. That's how it flows in MIG, stick, flux cored. On Tig, the electricity flows through the electrode also except that now that's the only function of it, the rod is held in your hand and electrode in the other.

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Description : What does three-phase current mean?

Last Answer : Three current sinusoidal waveforms equal in magnitude but with a phase shift of 120 degrees. 25

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Description : What is alternating current?

Last Answer : Bi-directional flow of current in a sinusoidal form with a positive and negative peak.

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Description : What is Direct Current?

Last Answer : Uni-directional flow of current.

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Last Answer : a) A pulsating uni-directional current

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Description : In a transistor, the conventional current flows from base to emitter. The transistor is (a) NPN (b) PNP (c) FET (d) None of these

Last Answer : (a) NPN

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Description : Current gain of a transistor which has collector current of 10 mA and a base current of 40 micro Ampere is: (a) 25 (b) 250 (c) 2500 (d) 25000

Last Answer : b) 250

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Description : A photodiode can switch its current ON or OFF in (a) nano second (b) milli second (c) micro second (d) centi second

Last Answer : (a) nano second

Forward current through a semi-conductor diode circuit is due to ________ (a) Minority carriers (b) majority carriers (c) holes (d) electrons

Description : Forward current through a semi-conductor diode circuit is due to ________ (a) Minority carriers (b) majority carriers (c) holes (d) electrons

Last Answer : (b) majority carriers