Wire Size for 17.72 Amps
Typical copper wire gauges for 17.72 amps across common run lengths on a 120V circuit, sized to keep voltage drop under 3% and respect the NEC 240.4(D) small-conductor rule. At 17.72A the load sits in residential-branch territory where aluminum is not a typical conductor, so the table lists copper only. Actual install sizing depends on conductor material, insulation/termination temperature rating, cable type, ambient and bundling derates, and local code.
17.72A Wire Gauge by Distance
| Distance | Copper Gauge | V-Drop (Cu) | NEC Status |
|---|---|---|---|
| 25 ft | 12 AWG | 1.75V (1.46%) | OK |
| 50 ft | 12 AWG | 3.51V (2.92%) | OK |
| 75 ft | 10 AWG | 3.3V (2.75%) | OK |
| 100 ft | 8 AWG | 2.76V (2.3%) | OK |
| 125 ft | 8 AWG | 3.45V (2.87%) | OK |
| 150 ft | 6 AWG | 2.61V (2.18%) | OK |
| 175 ft | 6 AWG | 3.05V (2.54%) | OK |
| 200 ft | 6 AWG | 3.48V (2.9%) | OK |
| 250 ft | 4 AWG | 2.73V (2.27%) | OK |
| 300 ft | 4 AWG | 3.27V (2.73%) | OK |
| 400 ft | 3 AWG | 3.47V (2.89%) | OK |
| 500 ft | 2 AWG | 3.44V (2.86%) | OK |
Copper gauges use the NEC 240.4(D) branch-circuit cap, not raw 75°C ampacity.
Also Calculate
Other Amperages
This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.