Re: VFD single phase 5hp

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Callcbm" <callcbm@...> wrote:

>
> ANy body now were to get a vfd for a 5hp using single phase. I found

one for

> 3hp single but not 5 hp single.
> will it hurt to use a 3hp on a 5 hp unit the lathe does and will not see
> using full power. Or would a Rotary converter be better.
> Thanks Randy
>

You will find the drive has a current limit.

At 460 volts, a 3-phase motor draws 1.27 amps per horsepower.
At 230 volts, a 3-phase motor draws 2.5 amps per horsepower.
At 230 volts, a single-phase motor draws 5 amps per horsepower.
At 115 volts, a single phase motor draws 10 amps per horsepower.
* These above are approximations.
746 watts = 1 HP

So, that 3 hp unit would be able to deliver just so many amps. About
3 hp worth.

You could get the motor to spin, but not get more out of it than a 3
hp motor.

Dave