Amps, breaker and wire by voltage
| Voltage | Current | Breaker (continuous) | Copper wire |
|---|---|---|---|
| 120 V | 20.0 A | 25 A | 10 AWG |
| 208 V | 11.5 A | 15 A | 14 AWG |
| 240 V | 10.0 A | 15 A | 14 AWG |
| 480 V 3-phase | 2.89 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 2,400 watts?
No. A 15 A circuit at 120 V supplies at most 1,800 W. Use a 20 A circuit (up to 2,400 W) or a 240 V circuit.
How many amps is 2,400 watts at 12 volts?
200 A at 12 V DC, before inverter losses (about 222 A through a 90% efficient inverter).