Wire Gauge and Voltage Drop
Calculate the minimum wire size from current, run length, and allowed voltage drop. See actual V drop and W loss for copper or aluminum at 12/24/48 V
Why round-trip length?
Voltage drop happens on both out and return conductors.
What % drop should I use?
3% is common for critical loads. Up to 5% for non-critical branches.
Can I use aluminum in a van?
It works but needs larger sizes, proper terminations, and corrosion control. Copper is simpler for small systems.