Electrical and engineering calculators
Voltage drop estimator
Estimate voltage drop in a copper conductor using a simplified resistance model.
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How it works
Uses copper resistivity at approximately 20°C and a simplified resistive model. It does not size conductors or verify code compliance; consult a qualified electrician for design.
Example
A 30 m one-way, 2.5 mm² copper run at 10 A has an estimated single-phase drop of about 4.14 V.