Wire Size for 384.5 Amps

Typical copper and aluminum wire gauges for 384.5 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. Actual install sizing depends on conductor material, insulation/termination temperature rating, cable type, ambient and bundling derates, and local code.

384.5A Wire Gauge by Distance

DistanceCopper GaugeAluminum GaugeV-Drop (Cu)NEC Status
25 ft 750 kcmil 750 kcmil 0.3287V (0.274%) check_circle OK
50 ft 750 kcmil 750 kcmil 0.6575V (0.5479%) check_circle OK
75 ft 750 kcmil 750 kcmil 0.9862V (0.8219%) check_circle OK
100 ft 750 kcmil 750 kcmil 1.31V (1.1%) check_circle OK
125 ft 750 kcmil 750 kcmil 1.64V (1.37%) check_circle OK
150 ft 750 kcmil 750 kcmil 1.97V (1.64%) check_circle OK
175 ft 750 kcmil no aluminum pick 2.3V (1.92%) check_circle OK
200 ft 750 kcmil no aluminum pick 2.63V (2.19%) check_circle OK
250 ft 750 kcmil no aluminum pick 3.29V (2.74%) 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.