voltage drop calculator

Voltage Drop

  • Calculator Main
  • Voltage Drop
  • Reel Selection

This is a calculator for the estimation of the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current. Please note this calculator assume the circuit is operate in a normal condition—room temperature with normal frequency.

The actual voltage drop may vary depend on the condition of the wire, the conduit being used, the temperature, the connector, the frequency etc. It is recommended that the voltage drop should be less than 5% under the fully loaded condition.

Required Data Entry
Select Material
Select Size
Select Voltage and Phase
Enter Cable Length Feet
Enter Load Amps

Calculated Results
Estimated Drop Volts
Load At Circuit End Volts
Voltage Drop Percentage
Conductor CMA

Basic Voltage Drop Law

Vdrop = IR

I : the current through the object, measured in amperes
R : the resistance of the wires, measured in ohms