Electrical Tool

Voltage Drop Calculator

Check branch and feeder voltage drop for HVAC equipment, condensing units, VFDs, electric heat, controls transformers, and BAS panels. This is built for field planning and troubleshooting when conductor size or run length is questionable.

Circuit Inputs

System voltage

Phase

Load current (A)

One-way length (ft)

Conductor material

Conductor size

Results

Voltage drop

0 V

Percent drop

Estimated voltage at load

0 V

Calculate to see whether the selected conductor is practical for the run.

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