Voltage Drop Calculator
Circuit Parameters
NEC Reference
NEC 210.19(A) Informational Note No. 4 and 215.2(A) Informational Note No. 2 recommend a maximum voltage drop of 3% for branch circuits and 5% total for feeder + branch circuits combined.
≤ 3% — Compliant
3–5% — Caution
> 5% — Exceeds limit
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