Re: VFD for series 1 bridgeport

> From: "Tim Goldstein" <timg@...>

> -----Original Message-----
>
> Any recommendations for a good, cheap VFD? I didn't know they
> convert to single phase. Cool! I do have a rotary phase converter
> but will be purchasing a VFD soon.

>Go to http://www.dealerselectric.com and check out the inverter drives
>(VFD). I have not tie to them other than being a satisfied customer. You
>will need to derate the unit by 50% to use it as a phase converter so for a
>2 hp mill you will want a 5 hp VFD.

Not completely correct- if you get a VFD that is rated for Single Phase
input then you can use it as rated. If you get one for Three Phase in
then you must derate it.

They simply take the input power into a rectifier then to a big
capacitor. The chopper uses the DC to generate the 3 phases. If you have
a unit raed for 3 phase in and you only drive it with single pahse it
will work fine, but you can only input 1/3 the power, hence the
derated output.

A VFD is one of those gadgets that once you have one you never
understand how you worked without it.

ron