Voltage drop by wire size (60 A, 50 ft, 240 V)
| Copper wire | Drop (V) | Drop (%) | Within 3% |
|---|---|---|---|
| 6 AWG | 2.95 V | 1.23% | ✓ |
| 4 AWG | 1.85 V | 0.77% | ✓ |
| 3 AWG | 1.47 V | 0.61% | ✓ |
| 2 AWG | 1.16 V | 0.48% | ✓ |
| 1 AWG | 0.92 V | 0.39% | ✓ |
Voltage drop = 2 × 50 ft × 60 A × resistance ÷ 1000. Keeping it under 3% on branch circuits (5% total) is the NEC recommendation in the informational notes to 210.19 and 215.2.
Frequently asked questions
Is 6 AWG enough for 60 amps at 50 feet?
It carries 60 A, but at 50 ft the voltage drop is 1.2%, which is acceptable.
Does the distance include the return wire?
No. Enter the one-way distance; the formula already counts both conductors.