CommercialNEC 2023 · 2026 · Updated Apr 2026

700 kcmil THHN Copper Ampacity

700 kcmil copper THHN: 520A base at 90°C, 460A usable after 110.14(C) termination limit.
Base520A
Usable460A
NEC Table310.16

Full derating calculation

Applications

700 kcmil copper handles high-capacity commercial and industrial feeders.

Voltage drop by distance

Distance (ft)240V Drop% DropVerdict
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NEC 2023 references verified April 2026