Wire Size for 0.5 Amps
Typical copper wire gauges for 0.5 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 0.5A 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.
0.5A Wire Gauge by Distance
| Distance | Copper Gauge | V-Drop (Cu) | NEC Status |
|---|---|---|---|
| 25 ft | 14 AWG | 0.0785V (0.0654%) | OK |
| 50 ft | 14 AWG | 0.157V (0.1308%) | OK |
| 75 ft | 14 AWG | 0.2355V (0.1962%) | OK |
| 100 ft | 14 AWG | 0.314V (0.2617%) | OK |
| 125 ft | 14 AWG | 0.3925V (0.3271%) | OK |
| 150 ft | 14 AWG | 0.471V (0.3925%) | OK |
| 175 ft | 14 AWG | 0.5495V (0.4579%) | OK |
| 200 ft | 14 AWG | 0.628V (0.5233%) | OK |
| 250 ft | 14 AWG | 0.785V (0.6542%) | OK |
| 300 ft | 14 AWG | 0.942V (0.785%) | OK |
| 400 ft | 14 AWG | 1.26V (1.05%) | OK |
| 500 ft | 14 AWG | 1.57V (1.31%) | 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.