Generac 12.5 Kw High voltage when load is applied

Portable standby generator troubleshooting and repair questions. (Gasoline, diesel, propane, natural gas)
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Joined: Sun May 12, 2019 3:17 pm

Thu Jul 04, 2019 3:23 pm

I have a portable 12.5kw generac. As soon as a load is applied the voltage jumps to 150v L-N. I've already changed the voltage regulator, governor and Diode feeding the Volatge regulator. attached is a video showing the voltage and frequency ant no load then with a space heater load.

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Location: Clawson, MI

Thu Jul 04, 2019 11:51 pm

Have you tested with another meter just to make sure it's not a meter issue?

This is normally the sign of a bad regulator, but since you changed it ready, I'm wondering if you're losing the input signal into the 11/22 circuit. If the sensing input into the regulator is lost, they will output whatever they can to try and compensate.

I'd test the 11/22 wires and see what the voltage is doing on the sensing circuit of the regulator.
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