Voltage Drop

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Voltage Drop

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Formula

ΔV ≈ I × (R cosφ + X sinφ) × L × multiplier

Cable R,X from tables; 1-phase vs 3-phase multiplier differs.

NEC / IEC cable practice

Assumptions & limits

  • Conductor temperature affects R
  • Power factor must be known or assumed
AluCalc 2026-07-12