Errorsfordays
Member
- Location
- USA
- Occupation
- Wind Turbine Technician
SOLVED
Although this thread changed significantly from the original post, I wanted to come back and update the solution to this problem.
I ended up testing DC amps as suggested by synchro, and only read high amperage on a single phase, as opposed to two phases when measuring AC amperage. This led me to focus on the downstream side of that single phase.
What was happening was a faulty current measuring transformer was burning up a resistor bank in the converter control unit every time someone would plug in a new CCU. The CT ohmed good when disconnected but had inconsistent resistance when connected due to this resistor bank being burned up. We opened the CCU and found the bad resistors. I got lucky and tested the feedback on the CT fast enough after putting in a new CCU that I saw the return voltage was bad, before the resistors burned up. A new CT fixed the issue completely.
Thank you guys for helping me out with that. The measuring DC amps suggestion was like a helivac in the right direction. I also learned a lot about troubleshooting bigger transformers so thanks for all the info early in the thread.
Although this thread changed significantly from the original post, I wanted to come back and update the solution to this problem.
I ended up testing DC amps as suggested by synchro, and only read high amperage on a single phase, as opposed to two phases when measuring AC amperage. This led me to focus on the downstream side of that single phase.
What was happening was a faulty current measuring transformer was burning up a resistor bank in the converter control unit every time someone would plug in a new CCU. The CT ohmed good when disconnected but had inconsistent resistance when connected due to this resistor bank being burned up. We opened the CCU and found the bad resistors. I got lucky and tested the feedback on the CT fast enough after putting in a new CCU that I saw the return voltage was bad, before the resistors burned up. A new CT fixed the issue completely.
Thank you guys for helping me out with that. The measuring DC amps suggestion was like a helivac in the right direction. I also learned a lot about troubleshooting bigger transformers so thanks for all the info early in the thread.