Had lightning hit a tree about 50 feet from my Generac 22kw standby generator and fry the evolution controller. I bought a new controller online, and the generator came back to life, but the transfer switch took a hit as well. It is an 80’s vintage Onan OT series switch, the damaged boards were the two that control the generator start and transfer. The voltage sensors were unhurt, the surge came in through the 12 vdc wiring rather than the power. Surprisingly, parts are available for the over 40 year old switch, but I am most likely going to rewire it and just use the 12vdc from the generator’s transfer switch output (which I didn’t use before) that is intended to control a Generac switch.
All I will use in the Onan switch would be the linear actuator and limit switches. I would just need to add a 12vdc relay to switch the generator or utility power to actuate it. Functionally, the Onan works like a Generac switch using line voltage to move the switch and limit switches to remove power from the actuator when it reaches full travel. But the Onan uses a knife switch rather than points to make the contact, and a real linear actuator rather the light duty pair of coils with a built in rectifier bridge like the Generac.
So the question is, should I just replace the whole switch with a new Generac switch, even though it’s much lower quality, or make the Onan switch work with the Generac control?
I went through this once when I installed the generator to replace the one of the same vintage as the switch, and decided to use the Onan controls for the transfer rather than the transfer switch output on the Generator then, but I’m thinking it might be time to retire the vintage electronic portion of the Onan Switch.
What do you guys think?
