GridBOSS and Generac whole-house generator

I was just informed by Signature Solar that the RSD relay port 2 cannot produce 12vdc to keep the battery at the starting battery for the generator charged. If you all find out something different, please let me know.

@wicksmith1 I was able to get the generator working after all. You can see this thread for details

- Generator wires (thick ones) go into "generator"

- IMPORTANT IF YOU WANT TO FOREGO ATC: Generator must be reconfigured for "2-wire start"

- inside generac panel: "VAC Load Supply" wire connects to one of the electric phases in the panel. two yellow wires no longer used. All wires from "DC Common", "+12V", "TRANSFER" are no longer used.

- connect two wires to your generator "2 wire start" PINs, as described here: https://diysolarforum.com/threads/replacing-generac-ats-with-grid-boss.94155/post-1290777 . These could be different on different models. If generator is reprogrammed for 2-wire start, shorting them should start generator, and un-shorting them should stop it

I was just digging through some old wiring diagrams for a similar project and saw this. The N1 and N2 wires are meant for utility sensing, but the GridBoss doesn't provide that 240V signal directly, so you’ll need to bypass those using a 2-wire start kit.

I had the same T1 charging issue and worked with Wolf River Electric to pull a separate 120V circuit just for the internal battery maintainer. Running that charging line independently of the inverter outputs ensures the battery stays topped off even when the system is in standby.