Wire Size for 396.83 Amps

Typical copper and aluminum wire gauges for 396.83 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.

396.83A Wire Gauge by Distance

DistanceCopper GaugeAluminum GaugeV-Drop (Cu)NEC Status
25 ft 750 kcmil no aluminum pick 0.3393V (0.2827%) check_circle OK
50 ft 750 kcmil no aluminum pick 0.6786V (0.5655%) check_circle OK
75 ft 750 kcmil no aluminum pick 1.02V (0.8482%) check_circle OK
100 ft 750 kcmil no aluminum pick 1.36V (1.13%) check_circle OK
125 ft 750 kcmil no aluminum pick 1.7V (1.41%) check_circle OK
150 ft 750 kcmil no aluminum pick 2.04V (1.7%) check_circle OK
175 ft 750 kcmil no aluminum pick 2.38V (1.98%) check_circle OK
200 ft 750 kcmil no aluminum pick 2.71V (2.26%) check_circle OK
250 ft 750 kcmil no aluminum pick 3.39V (2.83%) check_circle OK
300 ftExceeds available gauges
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.