How to Troubleshoot a Voltage Regulator with a 9V Battery

We are coming into summer season when we see many voltage regulator failures due to extreme heat…  Our own VP of Sales – David Vennie has a trick to save you money by quickly identifying if it’s a simple voltage regulator failure versus a major issue with your generator end.

This trick will help you determine if it is the voltage regulator or if it is something else major.

  1. Check the voltage on your main stator – ensure its reading at least residual voltage which is around 30V (>10V)
  2. Find your Voltage Regulator in the generator set (usually behind the control panel or in the generator end dog house)
  3. Locate your two exciter field wires usually labeled F1 & F2; F+ & F-; or + & –
  4. With the generator set running hook up your + & – to the 9V battery while still reading the voltage on your main stator with a mulitmeter
  5. We should see the voltage jump up to somewhere around your rated voltage (240V in this video). If it does, your voltage regulator is probably bad …
  6. If the voltage does not jump up, and you are sure you have the right exciter wires, you probably have a different problem in the generator end…