Re: [CAD_CAM_EDM_DRO] Re: VFD single phase 5hp

Al Daniel wrote:

>I read that a capacitor-run, 1-phase motor can be operated as an efficient 2-phase motor, with the capacitor removed, using a VFD designed for this mode of operation. This motor has no start-up switch. Can anyone comment on this type of VFD. Do the comments in this thread apply to this drive? Thanks! Al
>
>

Sure, this is true. Unfortunately, I have never seen a VFD that could
be configured
for 2-phase (90 degree) operation. it would generally require firmware
change
at the factory to do it. Depending on the voltage range of the motor
vs. the supply
line, it might also require an additional half-bridge power stage to be
added.
With 3-phase, you have 3 wires and 3 half-bridge power stages. For a
2-phase
motor, you could do it with 3 wires and 3 stages or 4 wires and 4 stages.

Jon