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EV Charger Cable Sizing Check

Estimate EV charger current, adjusted candidate cable capacity and AC voltage drop for a fixed charging circuit.

Inputs

Project inputs and assumptions

Range: 0.01–100,000 kW

Enter the charger electrical input power.

Range: 1–100,000 V

Use phase-to-neutral or line-to-line voltage consistent with phase factor.

Range: 0.01–1

Enter the operating power factor.

Range: 1–2

Use 1 for single phase or 1.732 for balanced three phase.

Range: 1–3

Use the conductor path factor for the selected AC model.

Range: 0.01–2

Enter the verified installation correction factor.

Range: 0.01–100,000 A

Enter the candidate cable ampacity before correction.

Range: 0.1–100,000 A

Enter the selected protective-device rating.

Range: 0–100,000 m

Enter one-way route length.

Range: 0–100,000 Ω/km

Enter verified conductor resistance for the cable.

Range: 0.01–100 %

Enter the limit selected from the applicable design basis.

Result

Adjusted cable capacity (A)
25.60
Capacity/protection margin (A)
-6.57
Estimated charger current (A)
32.17
Voltage-drop margin (%)
-0.18
Estimated voltage drop (%)
5.18
Estimated voltage drop (V)
11.92

Formula

Calculation logic

Formula definitions and substituted values.

Before relying on the result

  • Check a single-phase home charger feeder
  • Screen a three-phase charger cable against capacity and voltage drop
  • Verify charger nameplate data, continuous-load treatment, RCD/RCBO requirements, installation method and current Australian EV requirements before installation.

Related calculators

Verify charger nameplate data, continuous-load treatment, RCD/RCBO requirements, installation method and current Australian EV requirements before installation.