VFD

I just saw a 480v VFD on ebay. 10hp Just curious to know if you could use something like that for 220 volt 3phase motor from single phase?

My experience is 460 Volt VFD's won't work from 230. Not enough juice to charge the DC buss to full voltage. I get a UV (under voltage) on the display.

You can run 460 volts VFD's from 230 volts single phase if you can find a step-up transformer to increase 230 to 460 and if you de-rate the VFD by 1/3 to 1/2 (ie: use a 5 HP VFD to run a 3 HP motor).

I run my 30 HP 460 VFD on my 20 HP planer from 230 volts single via a 20 KVA step up transformer.

Howdy all,

I, too, have noticed the low prices on 460V VFDs on ebay.

Running one of these on 230V single-phase power via a step-up transformer sounds great, but I have a concern.

I'm wondering if ALL 460V VFDs can run on single phase 460V input. I know that some VFDs require that phase-loss detection be disabled to run on single-phase input.

Small (3HP or less) 230V VFDs often are able to run on single-phase input without being de-rated. I wonder if the same would be true of a 460V VFD.

Is there even such thing as 460V single-phase power in business and industrial applications? If not, I have a hard time imagining that any 460V VFD would have been designed to accommodate single-phase input.

Thanks,
Darron R. Birgenheier
Brantingham, NY

Darron, your concerns are valid. Single-phase 460 Vac power is rare, so many 460 Vac drives have phase-loss detection that you may or may not be able to disable. And even if you can disable it, plan on derating unless you can confirm otherwise.

There are actually a few applications where single-phase 460 Vac is common: pump-jacks (the oil pumps that go up and down), and bow-thrusters (used to maneuver large boats in port).

FYI, AC Tech's 460 Vac drives can be operated on single-phase power with the proper derating.

J Lauffer