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Unfused busbar tap-offs

Apostolos
Good afternoon.

I have a hotel where the consumer units of each room are fed through a 63A horizontal busbar using tap-offs along the way.

In the past the norm was to used 32A fused tap offs for each CU. The cable to each CU was rated at 32A as expected.

Could these tap-offs be unfused and the cables feeding the consumer units be rated at 63A ....same as the busbar?

Is this contrary to any regulation?

Thank you
Parents
  • 0
    You don't say what the CU in each room is equipped with.

    The requirement is that overload protection can be before or after the cable being protected (but short circuit protection must be before).

    This means that if the CU has an incoming breaker or if the total of all the outgoing breakers on a CU is less than the cable rating then the TEE off is protected against overload at the destination end and does not need protection at the source end.

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  • 0
    You don't say what the CU in each room is equipped with.

    The requirement is that overload protection can be before or after the cable being protected (but short circuit protection must be before).

    This means that if the CU has an incoming breaker or if the total of all the outgoing breakers on a CU is less than the cable rating then the TEE off is protected against overload at the destination end and does not need protection at the source end.

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