National Electrical Installation Standards

Standards as High as Your Own

Friday, March 13, 2020


Good Day to all at Code Question of the Day. Can splices be made in a panel? Some say yes, and some say no. What do you say ? Thanks.

Eddie Madison



Hi Eddie, thanks for participating. We get this a lot. The response to this question will hopefully provide clarity. This is a case where using Code-defined words and terms in the question would be very helpful. The term "panel" is used in the question and is presumed to mean "panel board" for the purposes of providing an answer. Article 408 contains requirements specific to panel boards, switchboards, and switch gear. Section 408.2 indicates that Article 408 applies, but also Articles 240, 250, 312, 404, and other articles could apply. Article 100 defines the term "panel board" as a single panel or group of panel units designed for assembly in the form of a single panel, including buses and automatic over current devices, and equipped with or without switches for the control of light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a wall, partition, or other support; and accessible only from the front. Based on the definition, panel boards are designed to be installed in a cabinet. Article 312 contains requirements for cabinets and cut outboxes. Section 312.8(A)(2) provides the rules related to conductors that are spliced within a cabinet or cut outbox, in your case, a cabinet that contains a panel board. Note that splices can be made in a cabinet containing a panel board if the total area of all conductors, splices, and taps installed at any cross section of the wiring space does not exceed 75 percent of the cross-sectional area of that space. Hope this is helpful.

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