rickbrennan
Plastic
- Joined
- Jan 19, 2018
- Location
- Boulder, Colorado, USA
I have a beautiful older Hardinge HLV (not HLV-H)that I got out of the back room of a university. Very little use on it. Runs on 440V. I've read tons of forum posts about different options for powering the lathe from 220v single phase power and settled on an Automation Direct GS2-23PO VFD (3HP rating) to manufacture the third leg and connecting the VFD output to three 1KV 440/220 step down transformers in reverse for step-up output. The transformers are wired in a delta-delta configuration. I tested the transformers individually before wiring them together and they all test good (220 in, 110 out). When I hook them up to the VFD with the disconnect at the lathe tripped (motor not connected), I immediately get an overload condition and resulting error and shutdown on the VFD. Tech support at Automation Direct wasn't familiar with this use case and couldn't help me diagnose the problem.
I don't want to experiment with this setup and risk smoking the relatively expensive VFD and hope someone out there is knowledgable about connecting transformers to VFDs and can help me think through what I've done wrong.
I've read about different wye and delta combinations. They describe the wiring and how to calculate things like phase current and phase shift, but I've not been able to read anything about running VFD waveforms through transformers and what considerations for the configuration options might be. For example, do I need to use a delta-wye setup instead of delta-delta? Or, is there a problem with inrush current running step down transformers in a step-up configuration? If so, are there settings on the VFD that would make this system work smoothly?
Also, if the delta-delta setup is ok, how do I test the transformers wired together to ensure I'm getting the desired behavior before I connect the VFD?
I don't want to experiment with this setup and risk smoking the relatively expensive VFD and hope someone out there is knowledgable about connecting transformers to VFDs and can help me think through what I've done wrong.
I've read about different wye and delta combinations. They describe the wiring and how to calculate things like phase current and phase shift, but I've not been able to read anything about running VFD waveforms through transformers and what considerations for the configuration options might be. For example, do I need to use a delta-wye setup instead of delta-delta? Or, is there a problem with inrush current running step down transformers in a step-up configuration? If so, are there settings on the VFD that would make this system work smoothly?
Also, if the delta-delta setup is ok, how do I test the transformers wired together to ensure I'm getting the desired behavior before I connect the VFD?