Re: VFD as 3Ph shop supply

On 2009-02-06, Pete C. <aux3.DOH.4@xxxxxxxx> wrote:

Ignoramus7868 wrote:

On 2009-02-06, Ignoramus7868 <ignoramus7868@xxxxxxxxxxxxxxxxxxx> wrote:
On 2009-02-06, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:
Guys, what are the limitations, precautions, or dangers of using a VFD
set to 60Hz as a "general" 3-phase shop supply.

Wiring length.

Say I had a total of 15HP worth of motors in the shop. If I installed a
15-20HP VFD, would there be any inherent dangers/damage potential in
switching motors in and out of circuit?

Can they work that way, or must they be connected to a motor during
their ramp-up time?

You can damage the drive by switching big motors on it, and also, long
wiring may create huge voltage spikes and damage your motors and
general insulation.


You can somewhat mitigate the effect of wiring length, any VFD manual
talks about this. Basically you would need to set up an inductor.


All of what Iggy said, plus larger VFDs often won't accept single phase
power input, and smaller VFDs are pretty reasonably priced these days
and I'm pretty sure using individual VFDs will cost less that buying one
monster single phase input capable VFD.

And it will be much more convenient.

I have very reasonably priced VFDs 3-5 HP nameplate rating for
sale. They work with single phase with some derating

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