Will RCCB and MCB trip for this case?

Thread Starter


Joined Aug 30, 2014
Please refer to the single line diagram below (third line) highlighted in yellow.

For the Live/earth fault of 63.75A, there will be a trip at RCCB since there is an imbalance between the live and neutral wire.

My question is will the 25A MCB trip? I think it will trip since the fault current is a lot highter than the rated 25A MCB. If MCB trips first, then RCCB will not trip?

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