Busbar
busbars, power distribution bar, positive busbar, negative busbar, earth busbar, battery busbar, terminal block, distribution block, DIN busbar
A busbar is a metal strip or block used as a common connection point to distribute current from the battery to multiple circuits. In a camper van, separate positive and negative busbars organise all power connections in one place, reducing cable clutter and voltage drop.
Copper or tin-plated busbars are rated 100–500 A. A positive busbar feeds fuse holders; a negative/earth busbar collects all ground returns, connecting with a single cable to the battery negative. Available as DIN-rail Wago blocks or bolted strip busbars.
FAQ
Do I need both a positive and a negative busbar?
Yes for a tidy install. The positive busbar distributes fused outputs; the negative busbar centralises all ground returns into one cable to the battery negative, eliminating voltage drop caused by multiple individual ground cables on the battery terminal.
How do I choose the right busbar current rating?
Add the maximum current of all circuits that could run simultaneously, plus 20 % safety margin. A 100 A busbar covers most van builds; 200–300 A for systems with a large inverter or electric heater. The busbar rating must exceed the main fuse protecting it.