- Can you put a 30 amp breaker on 12 gauge wire?
- What size Romex for a 30 amp breaker?
- How many amps can 12 AWG handle?
- What size wire do I need for 35 amps?
- How do I calculate what size wire I need?
You should not use a 30-amp circuit breaker on a 12-gauge wire. The circuit breaker installed on a circuit is of a specific size to protect a certain wire gauge. This higher current can damage the thinner wire, melt the insulation, cause short circuits, fire, and even lethal shock.
10 GaugeAnswer:Wire SizeAmpsWire Type8 Gauge40 AmpsFeeder and large appliance wire10 Gauge30 AmpsDryers, appliances, and air conditioning12 Gauge20 AmpsAppliance, laundry, and bathroom circuits14 Gauge15 AmpsGeneral lighting and receptacle circuits
20 AMPSSize & AMP RatingsNM, TW, & UF WIRE (Copper Conductor)SE CABLE (Copper Conductor)14 AWG – 15 AMPS8 AWG – 50 AMPS12 AWG – 20 AMPS6 AWG – 65 AMPS10 AWG – 30 AMPS4 AWG – 85 AMPS8 AWG – 40 AMPS2 AWG – 115 AMPS
Wire Size & Amp RatingsCopper14152012202510303584050
How do you determine cable wire size? Divide the voltage running through the cable by your target current. If, for instance, 120 volts will act on the cable, and you want 30 amps to run through it: 120 / 30 = 4. This is your target resistance, measured in ohms.