- #1
Josh111
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I am using a digital genset controller that to run and protect a generator. This controller has, in addition to other functions, timed overcurrent protection (1-30 seconds). The controller uses 5 amp secondaries. The generator is 83 amp. The 100 amp breaker I plan to use has a instantaneous trip rating of 300 amp.
My question is:
Since it is timed overcurrent, it may be possible that the amperage will be higher than full load amp for a while before there is a shutdown. Is it necessary, therefore to size the CTs at a rating higher than 100/5 to prevent them from burning up during a overcurrent situation? What percent, if any should they be oversized.
My question is:
Since it is timed overcurrent, it may be possible that the amperage will be higher than full load amp for a while before there is a shutdown. Is it necessary, therefore to size the CTs at a rating higher than 100/5 to prevent them from burning up during a overcurrent situation? What percent, if any should they be oversized.