Wire Size for 316.42 Amps

Typical copper and aluminum wire gauges for 316.42 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. Actual install sizing depends on conductor material, insulation/termination temperature rating, cable type, ambient and bundling derates, and local code.

316.42A Wire Gauge by Distance

DistanceCopper GaugeAluminum GaugeV-Drop (Cu)NEC Status
25 ft 500 kcmil 750 kcmil 0.4082V (0.3402%) check_circle OK
50 ft 500 kcmil 750 kcmil 0.8164V (0.6803%) check_circle OK
75 ft 500 kcmil 750 kcmil 1.22V (1.02%) check_circle OK
100 ft 500 kcmil 750 kcmil 1.63V (1.36%) check_circle OK
125 ft 500 kcmil 750 kcmil 2.04V (1.7%) check_circle OK
150 ft 500 kcmil 750 kcmil 2.45V (2.04%) check_circle OK
175 ft 500 kcmil 750 kcmil 2.86V (2.38%) check_circle OK
200 ft 500 kcmil 750 kcmil 3.27V (2.72%) check_circle OK
250 ft 750 kcmil no aluminum pick 2.71V (2.25%) check_circle OK
300 ft 750 kcmil no aluminum pick 3.25V (2.71%) check_circle OK
400 ftExceeds available gauges
500 ftExceeds available gauges

Aluminum is not typical for 10 AWG and smaller branch-circuit conductors in residential settings. Copper gauges use the NEC 240.4(D) branch-circuit cap, not raw 75°C ampacity.

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.