Chassis Ground Bar

There is normally no ground buss.
The battery is tied to the engine somewhere, then most chassis manufacturers connect the engine to the frame via braided cable.
Best is to trace the negative cable from the chassis battery to where it connects. It will depend on make of chassis.
If you are talking coach batteries, they quite often connect a group of negatives together behind the 12 volt power distribution panel normally located adjacent to the converter or inverter/charger depending on system.

Thank you. At least I will know where to start the search!

On our 06 Winnebago Outlook, there is one ground buss on the chassis rail behind or very close to the coach batteries. I'm not sure where they all come from. Maybe the Winnebago Wiring Diagrams , could help.

Ken

The Chassis *IS* the ground bar.

Mine is on the driver's side, up high, in the engine compartment.....Dennis