I know Generac doesn’t use 2 wire start but there is a workaround available. Engineer 775 on YouTube has done some Generac installs with the Sol Ark. One of his videos he completely eliminated the ATS and brought it in on the Gen leg. I have a Kohler 18k generator attached to my Sol Ark through an ATS on the grid leg.
In this configuration, I had a complete misunderstanding on how the Sol Ark works with the Generator and ATS. So the generator is completely isolated behind the ATS normally. Even if running it cannot pass power. The ATS is monitoring grid in an outage, the ATS will throw the contactor and now the gen is attached to the Sol Ark electrically. The Sol Ark will not immediately start the generator it will use solar and battery until they are exhausted to our setting of 30% SOC. At that time the Sol Ark will start the generator and charge the batteries and then shut down. About 1-1.5 hours for us. This cycle will repeat until power is restored and the ATS then reconnects to grid.
The point is the generator is going to be used in small increments to keep your batteries charged. It is not used primarily to power your loads as you are used to. This provides a significant reduction in fuel usage. During daylight, your solar will perform this so the generator will primarily be used at night when your batteries drop below 30% SOC.
It works well and saves us a lot of fuel usage instead of running 24/7 during a grid outage.
In this setup the Sol Ark uses a CT to monitor the grid leg and it can tell if the power coming down the grid leg is generator or utility power. When grid is restored the Sol Ark will see it and act accordingly.