Main electrical panel beside a subpanel with its cover removed

Microwave power requirements: 120 V grounded circuit, 15/20 A protection and why an OTR needs its own circuit

GE's requirement for countertop and OTR microwaves is a 120 V, properly grounded branch circuit with a three-prong grounding receptacle, protected by a 15 or 20 A breaker or time-delay fuse, and OTR models should always be on a dedicated circuit. OTR receptacles are normally in the cabinet above the unit. Other makers' sheets agree on 120 V and list 15 or 20 A; read the rating label and install sheet for the exact unit. New circuits are electrician work where your license requires it.

Cross-checked ~20 min moderateBrands: All

Before you start

Never cut off or bypass the grounding prong, and never use a two-prong adapter
No extension cords or power strips for a microwave
Running a new branch circuit or changing a breaker is licensed electrician work in many jurisdictions; refer it if it is outside your license

Diagnostic steps

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