This voltage drop reference table shows the voltage drop for a range of current values, assuming an one-way cable length of 20 m, a conductor area of 2.5 mm² and a resistivity (Ω·mm²/m) of 0.0175. Every figure is computed with the same engine that powers our Voltage Drop Calculator, so the numbers are exact.
| Current | Voltage drop |
|---|---|
| 2.5 A | 0.700 |
| 5 A | 1.400 |
| 7.5 A | 2.100 |
| 10 A | 2.800 |
| 15 A | 4.200 |
| 20 A | 5.600 |
| 30 A | 8.400 |
| 50 A | 14.000 |
| 70 A | 19.600 |
| 100 A | 28.000 |
How to use this table
Find the row closest to your current and read across to the voltage drop. For a value between two rows, the real figure sits between them — or enter your exact numbers in the Voltage Drop Calculator for a precise answer.
Need a value that is not in the table? — the Voltage Drop Calculator does it instantly, for free, with the formula and a worked example built in.
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