Two-Wire DC Voltage Drop Calculator
Account for both outgoing and return conductors.
Your result
EVERYDAYEnter your values and select calculate.
On this page How it works & practical examples
How to use the Two-Wire DC Voltage Drop Calculator
Account for both outgoing and return conductors. Resistivity is entered for the actual material and temperature; the example is not a universal material or wiring specification.
The calculation
Worked example
5 A over a 10 m one-way two-wire run at 0.0175 Ω·mm²/m and 2.5 mm² gives 0.7 V drop and 11.3 V at the load.
Assumptions and limits
DC resistive model only. No AC reactance, code-compliant cable sizing, ampacity or circuit protection. Voltage drop exceeding source voltage is incompatible with the fixed-current assumption and is rejected.
Common questions
Which inputs should I use?
Account for both outgoing and return conductors. Resistivity is entered for the actual material and temperature; the example is not a universal material or wiring specification.
What does the result exclude?
DC resistive model only. No AC reactance, code-compliant cable sizing, ampacity or circuit protection. Voltage drop exceeding source voltage is incompatible with the fixed-current assumption and is rejected.