10 AWG voltage drop at 25 feet
Computed voltage drop for 10 AWG copper conductors on a 25 ft one-way run.
1.45 V
drop on 10 AWG copper, 25 ft one-way, 24 A load · 1.2% of 120 V · 0.6% of 240 V
10 AWG at 25 ft by load
| Load | Drop | % at 120 V | % at 240 V | 3% rule (240 V) |
|---|---|---|---|---|
| 6 A | 0.36 V | 0.3% | 0.2% | OK |
| 12 A | 0.73 V | 0.6% | 0.3% | OK |
| 18 A | 1.09 V | 0.9% | 0.5% | OK |
| 24 A | 1.45 V | 1.2% | 0.6% | OK |
Vd = 2 × length × R × I ÷ 1000, R = 1.21 Ω/1000 ft (copper, NEC Ch. 9 Table 8). Aluminum is about 1.6× higher.
Same wire, other distances
50 ft · 75 ft · 100 ft · 125 ft · 150 ft · 200 ft · 250 ft · 300 ft
FAQ
What is the voltage drop on 10 AWG wire at 25 feet?
At 24 A (80% of its 30 A 75°C rating) 10 AWG copper drops 1.45 V over 25 ft one-way: 1.2% at 120 V or 0.6% at 240 V.
How far can I run 10 AWG at 24 amps?
To stay within 3% at 120 V, about 62 ft one-way; at 240 V about 124 ft.