CommercialNEC 2023 · 2026 · Updated Apr 2026

750 kcmil THHN Aluminum Ampacity

750 kcmil aluminum THHN: 435A base at 90°C, 385A usable after 110.14(C) termination limit.
Base435A
Usable385A
NEC Table310.16

Full derating calculation

Applications

750 kcmil aluminum handles high-capacity commercial and industrial feeders.

Voltage drop by distance

Distance (ft)240V Drop% DropVerdict
50 ft1.1V0.5%OK
75 ft1.6V0.7%OK
100 ft2.2V0.9%OK
150 ft3.3V1.4%OK
200 ft4.3V1.8%OK
250 ft5.4V2.3%OK
300 ft6.5V2.7%OK
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NEC 2023 references verified April 2026