What Size Wire for a Garage Door Opener?

A garage door opener typically uses a 20A / 120V circuit, which calls for #12 copper (or #10 aluminum) conductors and a #12 copper equipment ground per NEC Table 250.122. A residential garage door opener draws about 4-6A and plugs into a ceiling receptacle on the garage's 120V circuit. Since the 2017 NEC a receptacle is required for each vehicle bay (210.52(G)(1)), and 125V garage receptacles require GFCI protection (210.8(A)(2)); modern openers are GFCI-compatible. It normally shares the 20A garage circuit rather than getting a dedicated one.

A 20A single-pole (120V) breaker. The #12 copper conductors are matched to that 20A rating, and it must be a GFCI breaker (or GFCI protection ahead of the appliance). Do not oversize the breaker to a wire it does not protect: the breaker and the conductor go up together. Always confirm against the appliance nameplate, which lists the exact minimum circuit and maximum overcurrent device.

Yes. Current NEC requires GFCI protection for this appliance (NEC 210.8(A)(2), 210.52(G)). Use a GFCI breaker or a GFCI device ahead of it.

Yes. On the 75C column (the usual basis for aluminum), a 20A circuit needs #10 aluminum, versus #12 copper. Aluminum is common on larger circuits and services to save cost; apply antioxidant to the terminations, torque to the listed spec, and remember aluminum drops slightly more voltage on long runs.

Same answer: garage opener is another name for a garage door opener. It uses a 20A / 120V circuit with #12 copper wire and a #12 copper ground, GFCI protected. A residential garage door opener draws about 4-6A and plugs into a ceiling receptacle on the garage's 120V circuit. Since the 2017 NEC a receptacle is required for each vehicle bay (210.52(G)(1)), and 125V garage receptacles require GFCI protection (210.8(A)(2)); modern openers are GFCI-compatible. It normally shares the 20A garage circuit rather than getting a dedicated one.