National Electrical Installation Standards

Standards as High as Your Own

Wednesday, November 21, 2018


Dear sir,

As per NEC, I need to know that can I use one panel board for 04 buildings and each building has 6 maximum circuits used.(Two living rooms and one toilet in each building) OR should we need one panel board for each building? for your kind information the building is office staff housing and these 04 buildings are located next to each other with separate entrance which means no individual meter for each building. Please guide me.

Regard, Usman Ali Khan



Hey Usman thanks for your question. Using one panelboard to supply the circuits in 4 buildings can have many possible problems depending on the details of the installation. Each occupant must have ready access to the overcurrent devices for their occupancy unless continuous building management is provided as stated in 240.24(B) (1) & (2). Buildings supplied by branch circuits or feeders must generally be supplied by one of those unless special conditions exist as stated in 225.30. Installing a separate panelboard for each building will be a much better and safer installation even if you can meet the conditions that would allow you to use one for all of them.

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