Cable Voltage Drop Calculator

Calculate voltage drop for existing DC cable runs.

Voltage Drop Formula

VD = (2 x L x I x R) / 1000

VD = Voltage drop (V)
L = One-way length (ft)
I = Current (A)
R = Resistance (ohms/1000ft)

Voltage Drop Guidelines

Application Max Drop
PV Array to Inverter2%
Battery to Inverter2%
Charge Controller to Battery1%
Inverter to Loads3%