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VFD: 120v single phase input, 240v 3 phase output?

Dan1900

Aluminum
Joined
Jul 29, 2017
I was under the impression that a vfd needed 220v power to run a 3 phase motor. Now I'm not an expert by any stretch but I came upon this vfd on ebay:

Fuji FRN0005C2S-6U 1 HP 120V 1Ph In, 240V 3Ph Out, Frenic-Mini VFD Inverter
Fuji FRN5C2S-6U 1 HP 12V 1Ph In, 24V 3Ph Out, Frenic-Mini VFD Inverter | eBay

This seems like it would be perfect for my application. I have a 1hp 3 phase motor on my lathe that I would like to run on 120v if possible.

I don't currently have access to 220v, but will in the future. If I'm reading something wrong above and it actually won't work, can someone recommend me a vfd for my application?
 
I presently run four motors on VFDs, via 120 volt supply, this way.

Most of those are TECO drives, but the one hp one is Hitachi. I would have gone
with the inexpensive TECO for that lathe, but at the time apparently the manufacturer
of the TECO drives had some sort of production problem.

Am very happy with the Hitachi.
 
Let's try this:

Stand on the spot where the machine will sit.

Do you see:

The electrical panel?
OR
A dryer outlet?
OR
An electric range outlet?


IF yes to any of the above, 220 volts is right there.

Might be cheaper to install a proper adapter or proper outlet for the VFD required.
 
Thanks everyone, I guess you learn something new every day. Not sure where I got it in my head that you NEEDED 220v to run a 3 phase motor via VFD, but if it can be done with 120v thats perfect.
 
Ah, but you DO need 240V in to get 240V out, with one notable exception.

In SMALL drives, i.e. up to 1HP 230V, the VFD mfr can add a special front-end module called a "voltage doubler" circuit. So normally on a 240V input drive, the 240V is rectified to DC and comes out to about 330VDC on the internal bus of the drive. the transistors then fire that 330VDC in what's called a Pulse Width Modulated (PWM) pattern that makes the output "pseudo AC", meaning it's not really AC, but the motor acts as if it is, and for a motor controller, that's all that matters.

In the 120V input versions, the 120V is rectified to 165VDC, then fed into ANOTHER module, that "voltage doubler", that boosts it up to 330VDC, right where it would have been if it were a 240V feed. Technically, this can be done at any larger size and voltage too, it's not magic and anyone can google "voltage doubler circuit" to see the different ways of accomplishing it. But the thing is, the components to do it reliably at anything above 1HP @ 230V, will cost you more than just buying a simpler and rugged transformer to step the 120V to 240V anyway. So nobody bothers to make it larger than that.
 








 
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