National Electrical Installation Standards

Standards as High as Your Own

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Friday, March 30, 2018

Question:

Re: CQD answer published Thursday, March 22, 2017 -

That's not the question he was asking. He wasn't asking if there's a 200-amp breaker available for the service panel he is installing he is asking if a 200 amp service panel main load Center can support a secondary sub panel also rated at 200 amps! I believe the answer is no. A 200 amp main panel with a 200-amp main shut off cannot serve a two hundred amp sub panel. There may not be any NEC rule prohibiting this type of installation but I certainly do not install this way.

Oliver Allen

A

Answer:

Hey Oliver thanks for your comment. But the answer is still yes, it is allowed, and can be done for various reasons even though it might not be the best design. As you mention there is not a rule that prohibits distribution equipment from supplying other equipment of the same (or even a higher) rating. Multiple panelboards could be supplied from one of equal or even lower rating - the key is that they are properly protected and the loads are not exceeded and that there is a circuit breaker of the size need available.

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