Purpose of Local breaker back-up relay; type -CTIG

Purpose of Local breaker back-up relay; type -CTIG
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To safe guard against the drastic consequences of failure to clear faults rapidly, many power supply authorities install 2 independent systems of protection for major transmission lines. There remains however the possibility of the circuit breaker itself failing to operate and this hazard is traditionally covered by remote breaker back-up.; CTIG relay is a 3 phase or 2 phase and earth fault instantaneous over current unit intended for use with a time delay to give back-up protection in the event of a circuit breaker failure. A particular feature of the CTIG relay is a fast reset, which enables the time delay to be set closer to the breaker trip-time. 
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Last Answer : Answer: D

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Last Answer : Answer: A

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Last Answer : Answer: C

When an AC or a DC motor fails to start, the FIRST step in troubleshooting should be to check the ____________. A. motor windings for obvious opens B. motor controller leads for continuity C. fuse or circuit breaker D. motor controller leads for grounds

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Last Answer : Answer: C

Component F in the illustrated device is for _________. EL-0033 A. short circut protection B. latching the trip unit closed after resetting the breaker C. overload protection D. providing a flexible connection between the input terminal G and the tripping unit E

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Last Answer : Answer: C

An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Description : An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Last Answer : Answer: C

Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine _____________. A. slightly less than the line frequency B. the same as the line frequency C. slightly greater than the line frequency D. all of the above

Description : Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine _____________. A. slightly less than the line frequency B. the same as the line frequency C. slightly greater than the line frequency D. all of the above

Last Answer : Answer: C