National Electrical Installation Standards

Standards as High as Your Own

 
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Monday, October 31, 2022

Question:

Hi CQD, I installed a 2-pole 40-amp breaker in an unfinished basement breaker panel. I ran 8/3 NM-B through the basement and up inside an interior garage wall to a box with a 14-50R flush receptacle to match what comes on most EV chargers. The homeowner purchased the EV charger which had the 14-50P plug on it, instead of getting the 32-amp charger we originally discussed. The 32-amp charger was the correct one for the circuit I installed. The inspector stated the circuit was not sized for the larger EV charging unit. The manufacturer's installation instructions for the larger charger requires a 50-amp circuit and 50A breaker. Technically I only installed the circuit and receptacle, so the inspector should only check my installation. The product getting plugged in should not factor into the inspection outcome. (1) Is it permissible to install a 50A receptacle on a 40A rated circuit? (2) Where does the inspector's jurisdiction end?  

Thank you, Rich Cressotti
A

Answer:

Hi Rich, thanks for the information and the questions.

 

Regarding the question on circuit and receptacle rating. Both Section 210.21(B)(3) and Table 210.21(B)(3) permit a 50A rated receptacle to be supplied by a 40A rated circuit. The receptacle and circuit rating combination you describe would be permitted.

 

Regarding the jurisdiction of the electrical inspector, this becomes and AHJ determination based on the information they have at the time of the inspection, and any State or local rules.

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