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Voltage Drop Calculator

Calculate voltage drop for a branch circuit and verify compliance with NEC 3% recommendation.

Panel to load; round trip doubled automatically

Voltage Drop2.97V
Drop Percentage

2.48%

Compliant (under 3% NEC branch circuit recommendation)

Formula: V_drop = (2 × L × I × R) / 1000 • Reference: NEC 210.19(A) FPN 4 (3% branch, 5% total)

For reference only. Verify with your local building code and a licensed professional before making decisions.

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