Re: Harmonics anyone?
"I am troubleshooting (3) HVAC control cabinets. Each cabinet is fed by its own 120V circuit, but all 3 share the same neutral. There is one single phase 120/24 VAC control transformer per cabinet. The transformer primary shows high levels of 3rd order harmonics, and at random times of the day, the N-G voltages are peaking at over 5 volts. They have burned up numerous boards."
Are these transformers Auto-transformers?