National Electrical Installation Standards

Standards as High as Your Own

 
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Friday, July 29, 2022

Question:

Greetings CQD,

Thanks for all you do. The information is terrific. I heard that there is no longer a 42-circuit limit on panelboards. Is this correct? Are there any other limits on the amount of circuits that can be installed in a panelboard? Your opinion would help.

Paul Cohn

A

Answer:

Hello Paul,

Thanks for the question. You are correct. The 42 circuit limitation for panelboards was removed a few Code cycles ago. In Section 408.54 there is language that relates to circuit limitations in Panelboards and it reads as follows: A panelboard shall be provided with physical means to prevent the installation of more overcurrent devices than that number for which the panelboard was designed, rated, and listed. For the purposes of this section, a 2-pole circuit breaker or fusible switch shall be considered two overcurrent devices; a 3-pole circuit breaker or fusible switch shall be considered three overcurrent devices. So as you can see, the number of circuits is limited by the manufacturer and to what the equipment is listed for. There are panelboards with the designation "CTL" which, as we understand it, stands for circuit limiting. Follow the manufacturer's requirements for this equipment. 

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