Estimate voltage drop, voltage drop percentage, final voltage, wire resistance, wire gauge, circuit watts, and power loss from amps, voltage, distance, phase type, and copper or aluminum wire.
Wire resistance:
The calculator uses wire material and circular mil area to estimate resistance over the entered distance.
Voltage drop:
The load current, distance, material constant, and wire size are used to estimate voltage drop.
Final voltage:
The calculator subtracts the estimated voltage drop from the starting system voltage.
A voltage drop calculator helps estimate whether a wire run may lose too much voltage before the load.
It can help with branch circuits, feeders, outdoor runs, shed wiring, garage circuits, RV wiring, solar wiring estimates, low-voltage circuits, lighting, and general electrical planning.
Your result shows estimated voltage drop, voltage drop percentage, final voltage at the load, wire gauge, material, current used, one-way distance, round-trip distance, power loss, and comparison scenarios.
Voltage drop is the loss of voltage that happens as current flows through wire resistance over distance.
Many electrical planning estimates use 3% as a common target, but the right target depends on the equipment, circuit type, local code, and project requirements.
You can reduce voltage drop by using larger wire, shortening the wire run, reducing current, increasing voltage where appropriate, or using copper instead of aluminum.
Yes. Longer wire runs have more total resistance, which usually increases voltage drop.