AC Systems

240V Voltage DropCalculator

Calculate voltage drop for 240V AC circuits including dryers, ranges, HVAC, and EV chargers. Professional calculator with NEC compliance.

AC Circuit Parameters

NEC Chapter 9 Table 9 values

Calculation Results

Pass
Voltage Drop
4.41V
1.84%
Voltage at Load
235.6V
of 240V source
Power Loss
48 W

Excellent - Meets NEC recommendations

240V Applications

  • Electric dryers and ranges
  • HVAC systems
  • EV charging stations
  • Pool and spa equipment
  • Welding equipment
  • Workshop machinery

AC Formula

Single Phase:
Vd = 2 × I × Z × L / 1000
Three Phase:
Vd = √3 × I × Z × L / 1000

Voltage Calculators

240V Voltage Drop Calculation Guide

About 240V Systems

240V AC systems are commonly used in residential appliances and light industrial equipment. Proper voltage drop calculations ensure equipment operates efficiently and safely within rated tolerances.

The NEC recommends limiting voltage drop to 3% for branch circuits and 5% total for the combination of feeder and branch circuit. For AC systems, this translates to a maximum drop of 7.2V for branch circuits.

Calculation Considerations

AC voltage drop calculations must account for both resistance and reactance of the conductors. The power factor of the load affects the effective impedance, making higher power factor loads more efficient from a voltage drop perspective.

For 240V systems, common wire sizes range from #10 AWG for light loads to 4/0 AWG for heavy feeders. Always verify ampacity requirements alongside voltage drop calculations.