Electrical guide

Voltage drop guide

Voltage drop is the loss that happens along the cable run. The right limit depends on whether the circuit is low-voltage DC or mains AC.

Low voltage

12V and 24V systems are sensitive to drop because even a small loss is a large percentage of the supply.

Mains circuits

230V circuits can usually tolerate a different percentage, but the load and application still matter.

Wire size

Larger conductor areas reduce voltage drop, especially on long runs with higher current.

Related pages

Electrical pages

Voltage drop calculator

Open the main voltage drop calculator.

Open calculator

Wire size calculator

Use the inverse calculation to size a conductor.

Open page

How much voltage drop for 12V?

See a 12V-specific target example.

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