Electrical / DC wiring

Voltage Drop Calculator

Estimate DC wiring losses or find the minimum conductor size for a target voltage drop.

Supply and load

System voltageChoose a preset or enter a custom voltage.CurrentExpected continuous circuit current.

Cable run

One-way cable lengthThe return conductor is added automatically in two-wire mode.Length unitConductor materialCircuit typeMost DC circuits use the two-wire setting.

Conductor size

Cable size formatConductor areaCross-sectional area of one conductor.

Results

Voltage drop5.75%

Excessive — A larger conductor is advisable.

Voltage drop: 0.69 V
Voltage at load: 11.31 V
Cable resistance: 0.06896 Ω
Power lost: 6.9 W

These are theoretical DC estimates using conductor resistivity at approximately 20°C. Real installations vary with conductor temperature, terminations, connector resistance, strand construction and installation conditions. Confirm cable ampacity, protection and local requirements separately.