NEC – % Voltage Drop Calculation

Step – I Calculate % Voltage Drop if cables are parallel

Vp% = (100 * Vd * 2) / Vs

Where:

Vp% = permissible voltage drop %.

Vs = supply voltage, in volts

Step – II Calculate % Voltage Drop

Vp% = (100 * Vd) / Vs

Where:

Vp% = permissible voltage drop %.

Vs = supply voltage, in volts