Wire Size for 274.33 Amps

Typical copper and aluminum wire gauges for 274.33 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.

274.33A Wire Gauge by Distance

DistanceCopper GaugeAluminum GaugeV-Drop (Cu)NEC Status
25 ft 300 kcmil 500 kcmil 0.5884V (0.4904%) check_circle OK
50 ft 300 kcmil 500 kcmil 1.18V (0.9807%) check_circle OK
75 ft 300 kcmil 500 kcmil 1.77V (1.47%) check_circle OK
100 ft 300 kcmil 500 kcmil 2.35V (1.96%) check_circle OK
125 ft 300 kcmil 500 kcmil 2.94V (2.45%) check_circle OK
150 ft 300 kcmil 500 kcmil 3.53V (2.94%) check_circle OK
175 ft 350 kcmil 750 kcmil 3.52V (2.94%) check_circle OK
200 ft 500 kcmil 750 kcmil 2.83V (2.36%) check_circle OK
250 ft 500 kcmil no aluminum pick 3.54V (2.95%) check_circle OK
300 ft 750 kcmil no aluminum pick 2.81V (2.35%) 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.