National Electrical Installation Standards

Standards as High as Your Own

Friday, October 28, 2022


Hi Code Question of the Day. Do all branch circuits/electrical wiring for a dwelling unit, have to be wired to the service panel of that unit? For Example: the branch circuits/electrical wiring coming from apartment 1 goes into apartment 2. This electrical wiring is live and is wired through service panel of apartment number 1 and not the service panel for apartment number 2. Thanks, Augie Perez


Augie, this situation comes up quite often when upgrading a service on an older, existing two/multi-family dwelling. The NEC does address this issue through the rules in Section 240.24 for fuse and circuit breaker locations on a premises. However, if all the facets of 240.24(A) & (B) are complied with, this may fall outside the scope of the NEC, and becomes a consumer protection/payment and metering issue. For these situations, it is always advisable to contact the local AHJ and Utility to see how they address these issues.

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