Voltage Drop Calculator
Use this voltage drop calculator to estimate voltage loss along a cable. Enter source voltage, current, cable length, conductor size and material and review estimated voltage drop and remaining voltage.
Resistance values are typical for copper at room temperature; actual values vary slightly with temperature and conductor material.
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How it works
Vdrop = 2 × current × resistance-per-length × length (for single-phase round trip)How to use the Voltage Drop Calculator
Start by entering source voltage, current, cable length, conductor size and material. Keep the units consistent and check that each value belongs to the same question.
The result gives estimated voltage drop and remaining voltage. Temperature, connections and installation method affect actual performance. Use it as a guide and check any instructions, rules or professional advice that apply.