Why low forward power relay used in parallel to reverse power relay?

1 Answer

Answer :

A small steam leak through CIES valves will keep the machine floating on to grid at low power. So even if turbine trip, relay picks up, there is no trip actually. So low forward power relay (0.54%) used to detect the condition. 

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Description : Diesel generators #1 and #2 are operating in parallel at near full load capacity. Diesel generator #1 suddenly trips out mechanically due to low lube oil pressure. The reverse power relay functions ... all nonvital circuits. D. Secure alarms, reset reverse power relay, and restart #1 engine.

Last Answer : Answer: C

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Last Answer : Answer: D

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Last Answer : reverse bias diode

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Last Answer : Answer: B

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Description : What is reverse power relay?

Last Answer : Reverse Power flow relay are used to stop the flow of power from grid to station generator when the generating units are off.

Description : What is reverse power relay?

Last Answer : Reverse Power flow relay are used in generating stations' protection.  A generating station is supposed to feed power to the grid and in case generating units are off, there is no generation in the ... power from grid. To stop the flow of power from grid to generator we use reverse power relay.

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