Re: [CAD_CAM_EDM_DRO] Inverters/phase converters

> I was told by the EMS/ Yaskawa people that a 3 phase drive powered by

single phase will work if the output of the unit is derated.

>

The Hitachi SJ100 5hp inverter is derated to 3hp for single phase. Other
5hp inverters I looked at are also derated to 3hp for single phase.

>

If you can keep the rectifiers cool, I think you could drive them really
hard. Most VFD's come with temp sensors and fans, some don't Perhaps a fan
retrofit would help the device live if it came with out one.

>

Nice thing about Hitachi drives is a built-in temp switch to turn a fan on.

> One other idea would be to step up voltage to the device so current is

lower through the rectifiers? I'm not sure if this would work. Many VFD's
will accept 440 volts?

>

The 440V inverters are more money for the same size - maybe due to higher
voltage rated IGBT's. Maybe just because they can get away with charging
more.

Doug