Voltage Drop Calculator

What is Voltage Drop?

Voltage drop describes how the supplied energy of a voltage source is reduced as electric current moves through the passive elements (resistive elements) of an electrical circuit.

Formula

The basic formula for single-phase voltage drop is:

$$ VD = \frac{2 \times L \times R \times I}{1000} $$

Where:

• VD is Voltage Drop (Volts)
• L is One-way length of the wire (Meters or Feet)
• R is Resistance of the wire per 1000 units (Ohms/kft or Ohms/km)
• I is Load Current (Amperes)

Note: This calculator uses simplified resistance values for standard copper/aluminum wire gauges.