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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
    What is protecting the bus bar, and would it be acceptable for it all to lose power together due to a fault in one circuit fed by an unused tap?

    If the fuses or breakers supplying the busbar co-ordinate with the protection required for the cable, it is certainly possible.


    The convenience of it being broken up in terms of isolation for finding  faults, or indeed to shut off one branch for repair, and keep the rest energised is lost, but this may be acceptable.
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  • 0
    What is protecting the bus bar, and would it be acceptable for it all to lose power together due to a fault in one circuit fed by an unused tap?

    If the fuses or breakers supplying the busbar co-ordinate with the protection required for the cable, it is certainly possible.


    The convenience of it being broken up in terms of isolation for finding  faults, or indeed to shut off one branch for repair, and keep the rest energised is lost, but this may be acceptable.
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