TiTillIdie
Plastic
- Joined
- Aug 27, 2015
Our shop fluctuates a lot on our CFM needs. We currently have a 20HP 77 CFM Ingersoll rand compressor running modulation mode @ 90 PSI, about 22-24 amps. We have kicked around a few ideas like getting 2 10hp and running them one or two, but I really like the idea of a VFD. I cannot find anything that PROVES there is power savings by running the motor slower. We have an old machine at the shop that has a VFD to run the spindle. We turned it on at like 100 RPM, 6 amps, cranked it to 1000 rpm, 6 amps, cranked it to 3600 rpm and still 6 amps. I know its not under load, but I would have thought this would be proof that its using less amps to run. So if a 20HP VFD is running at 5000 rpm and slows down to 2500 RMP, is it really using less power? Has anyone replaced their screw compressor with a VFD and seen a difference in their power bill?