Thanks, I tried to do it a couple of ways which turned out to be more complicated than it needed to be. I ended up using a typical 24VDC automotive relay and a SPDT switch for auto-start / default operation. I like to make things so if there is a controller failure you simply unplug the controller and flick one switch to go back to default operation. The way I set this up is basicly using most of the genset controls, I just use the outputs of the controller and a relay to mimic S1.
Things I still need to setup
The AC interrupter (controller has a output for this)
High temp, Low oil alarms with shutdown, 831A has switches for these, 802A/803A will have actual oil pressure and coolant temp on the controller. (controller has a input for this)
The current transformers for L1-L2 and N so the controller can accurately display watts per leg/N and alarm / shutdown on programmed limits.
Correct the fuel level indication, the resistance curve is completely programmable and will figure out how to configure the No fuel switch into the whole system.
connect the wire to the charge alternator and program actions if it fails to charge the battery or the batteries are failing.
Install the MPU, this isn't necessary as it turns out but it's only $40 and 3 wires. I think it would be good to have that info for logging and troubleshooting remotely.
Once I have the Cellular gateway I'll create a read only account so people can login to the webpage and monitor what the genset is doing to see how useful that is for many reasons.
Then to find and make a professional type wiring harness with plugs a person can connect/disconnect easily.