# A little confused, need help



## Davd Flowers (Jan 22, 2017)

Im looking at this vfd http://www.ebay.com/itm/2-2KW-220V-...dbdfd4d&pid=100005&rk=6&rkt=6&sd=111490143307
to power a 2 or 3 hp motor on my mill.  Single phase 220 in and 3 ph out.  Will it work?


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## Bob Korves (Jan 22, 2017)

It should work OK.  It common to use a VFD somewhat larger in capacity than the motor, especially with Chinese VFD's.  So, for a three HP motor it might be worth going to a bit bigger VFD than the one you are looking at.  But it is rated for 2.2 KW, which is 3 HP...


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## Davd Flowers (Jan 22, 2017)

I figured I had better ask before pushing the button.  It was the way they list the input voltage that had me a little concerned..


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## Ulma Doctor (Jan 22, 2017)

on a milling machine you are not likely to use the full HP of the motor.
I also would consider using a VFD that is Overrated , if the mill ig going into heavy use.

I put a similar VFD on my Shenwai 1236 lathe. i got a 3hp motor and a 3hp VFD.
my lathe doesn't see continuous, heavy use. 
the VFD has survived for 2 years now without a hitch
you results may vary


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## wawoodman (Jan 22, 2017)

Is the question one of concept, or suitability of this particular unit?

I have a Hitachi for my mill, and it works fine. I'm always a bit leery of low-price electricals. For something like a DRO, no big deal. But 220 line voltage, well...

Just my opinion, though.


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## Davd Flowers (Jan 22, 2017)

wawoodman said:


> Is the question one of concept, or suitability of this particular unit?
> 
> I have a Hitachi for my mill, and it works fine. I'm always a bit leery of low-price electricals. For something like a DRO, no big deal. But 220 line voltage, well...
> 
> Just my opinion, though.



I went ahead and ordered it, hopefully it was not a mistake.
Ive seen some of these vfd's rated at 2.2KW, but at only 3-4 amps. This one is rated for 10 amps.  On a 3hp motor wired low voltage amp draw is 7.2 amps, and on a 2 hp motor wired the same it would be 3.9 amps, so I think I should be ok??
  Further down in the e bay listing it said something about 308v normal input voltage, thats where I started second guessing things..


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## wa5cab (Jan 24, 2017)

The 308 could have been a typo.  208 VAC is what you get line to line with 120/208 wye system.


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