National Electrical Installation Standards

Standards as High as Your Own

Wednesday, March 28, 2018


Can you shed some light on a situation I have always thought to be fine. I have a #6-3 Romex wall oven circuit that is stand alone in the kitchen. I also have a built in microwave in the cabinet above. As I read it 210.19(A)(3) exept1 allows me to tap off of the oven circuit to supply that microwave. As long as the requirements are met in exception 1 overriding 240.21

Donny Thompson



Hey Donny thanks for your question. Actually 240.21(A) references 210.19 so you are not really "overriding" it. Conductors, for household cooking appliances, that have an ampacity of at least 20 amperes can be tapped from a 50 ampere branch circuit meeting all the conditions of 210.19(A)(3). The words used are "wall mounted" electric ovens so the microwave would need to be that type. Make sure that if a protective device rating is marked on the appliance it is not exceeded as stated in 422.11(A) and that any instructions are complied with as stated in 110.3(B).

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