Thanks so much. No wires from the pd9100 to the DC panel just uses the same wires from the battery. These are small gauge but I guess not much power is needed at the dc panel.
If the batteries were ever removed the circuit would have to be closed between the positive and negative battery wires.
I had plenty of #2 wire but it does not fit in the pd9100. I guess they call for #4 so even better that the charger is closer to the batteries.
I’m still a bit confused by the wiring from the batteries to the panel. I think I have figured out the two disconnect switches though. One triggers when the starter is on and charges the batteries from the chassis. (solenoid) The other sends a start voltage to the generator if the starter is off it comes from the batteries if on from the chassis.
I was thinking one way street so knowing the wires are two way makes a big difference.