Amps, breaker and wire by voltage
| Voltage | Current | Breaker (continuous) | Copper wire |
|---|---|---|---|
| 120 V | 5.0 A | 15 A | 14 AWG |
| 208 V | 2.9 A | 15 A | 14 AWG |
| 240 V | 2.5 A | 15 A | 14 AWG |
| 480 V 3-phase | 0.72 A | – | – |
Breaker sized at 125% for continuous loads (NEC 210.20). Motors and electronics draw more current than watts ÷ volts because of power factor.
Frequently asked questions
Can a 15 amp circuit handle 600 watts?
Yes. A 15 A circuit at 120 V supplies 1,800 W, or 1,440 W for continuous loads, so 600 W fits.
How many amps is 600 watts at 12 volts?
50 A at 12 V DC, before inverter losses (about 56 A through a 90% efficient inverter).