Calculate voltage drop for single-phase and three-phase circuits. NEC (Art. 210/215) and IEC (60364-5-52) methods. Copper and aluminium conductors.

// INPUTS

// Results update automatically as you type

// CIRCUIT PARAMETERS

System Type

Voltage (V)

Equipment Rating

Rating Unit

Power Factor

Efficiency (for kW / HP only)

Derived Full Load Current (A)

Calculated from rating: used for VD

// CABLE PARAMETERS

One-Way Length (ft / m)

ft (NEC)

Conductor Size

Conductor Material

Voltage Drop -V

Voltage Drop (%) -%

Receiving End Voltage -V

NEC Limit (branch/feeder) 3% / 5%

Status -

Max Length @ 3% VD -ft

Max Length @ 5% VD -ft

Disclaimer: For reference and preliminary estimation only. Verify results against the applicable code, project specification, and equipment data before use in design documents. Found an error or an outdated reference? Let us know at [email protected].

Please check inputs, all values must be positive.

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CableSched-LMX

Full cable schedule generator: automates ampacity checks, voltage drop across all circuits, and routing references at project scale.

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Voltage Drop Calculator