Electrical design
Voltage dropVoltage drop calculator
Estimate the voltage drop on a DC or AC circuit, then check whether the conductor size is reasonable for the distance and current.
Best for
- 12V systems
- 24V systems
- 230V circuits
A 12V circuit with a 5A load over 8 m one-way
The loop length is twice the one-way distance, so the cable length used in the calculation is 16 m.
Example build-up
Supply: 12 V, current: 5 A, length: 8 m one-way, copper cable, 2.5 mm2 conductor.
Result
Voltage drop is approximately 0.56 V, or 4.7 percent.
Enter the circuit details
Loop length is twice the one-way run for the calculation.
What each input means
System voltage
Choose the supply voltage that matches the circuit you are designing.
Current and length
Current and one-way length drive the drop calculation more than the nominal voltage does.
Wire size
Use the wire size field to compare the current drop against a practical conductor area.