Code Q&A: Temperature Limitations of Equipment

Q. How is the conductor ampacity for Type MC cable determined per the NEC?


See the answer below.









This answer is based on the 2017 NEC.

A. Conductor ampacity is calculated on the 90°C insulation rating of the conductors; however, the conductors must be sized to the termination temperature rating in accordance with Sec. 110.14(C)(1) [330.80].


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