Shiny Steve
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Hello every one, I have just picked up a larg progress drill. It's 3 phase and I'm looking at getting a cheap vfd to run it. Dose any one have any opinions or experience with this? Thanks Steve.
what are the implications if its 400v only?
Here's for that chaps, what are the implications if its 400v only?
I've posted that link a few times, and it's an easy tweak to do. I did it with a Siemens Micromaster drive and an old Brook motor I had, worked fine. I'd say it's ideal to do on a drill where you can just gear up if you need higher speeds, but get full torque at lower speeds.I'll stick my head above the parapet and wait for the howls of derision on this one...
My Elliott mill has 400V motors. I run them off of 230V VFDs. They are not dual voltage motors and I couldn't see an easy way into the windings to pick out the star point. I enquired about getting them re-wound - would be cheaper to buy a new motor! I found an article on inverterdrive.com about running 440V motors on 230V. Nothing will blow up! A VFD ramps down the voltage as the frequency reduces and there are parameters you can tweak to change how this behaves (at least there are on the WEG drives that I'm running). The VFD normally ramps down the voltage as the output frequency drops below 50Hz, so you reprogram this so you get full voltage at a lower frequency. You then get full torque at 30Hz but above this frequency the motor runs at lower power, so less torque.
Given that my mill isn't in a production environment and I can take lighter cuts if it struggles (which generally it doesn't) it works perfectly for me, and has done for a couple of years.
Rob