Based on the 2020 NEC.
Question: Does the wiring entering a switchboard need to enter in the same vertical section that contains the circuit breaker it is terminated on?
See answer below.
Answer: Yes
Explanation: Section 408.3(A)(2) of the NEC states, "Other than the required interconnections and control wiring, only those conductors that are intended for termination in a vertical section of a switchboard or switchgear shall be located in that section." There is one exception that allows conductors to travel horizontally through vertical sections if they are isolated from busbars by a barrier.
Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected].