Re: VFD recommendations for Bridgeport W/gecko 201's (was Boss 3)

> "In fact, life can be made easier on the VFD and the motor by
> soft starting and stopping the VFD and not using the anti-plugging
> solenoid/contactor."
>
> now will that shut the power off entirely to the machine? I'd

still

> want to be able to move/control the axis which are going to have

to

> have the power on from the VFD. Or am I way off base here? Can the
> powersupply (rectifier) for the stepper's and the Geckos be

converted

> to 220 single phase or 110v?

On this my intention was to take the 220VAC and run the two legs
through the main on/off switch on the small enclosure. Then through
the existing fuses. From there the two legs would both go to the
VFD. Out of the VFD would go to thru the plugging
contactor/solenoid to the direction switch on the head, to the
motor. To keep the loads down on the VFD, I planned on using the
switch just for direction, and turning on and off the VFD from the
inputs available to it. That way it ramps up/down nicely. Of
course, you could still bang the switch from full forward to full
reverse, the plugging contactor should still work, and you just beat
up the VFD a little more.

If you want to keep everything else 3 phase and run it off the VFD,
you would just switch the order and run it 220 single phase ->
Fuses -> VFD -> To the rest of the machine. The full load the the
VFD then could exceed the 2HP it is rated, but only if you loaded
the spindle motor pretty hard.

I planned on running the Geckos from a 110V source. You generally
are not supposed to split the legs of a 220 single phase to
accomplish this. It has something to do with the breakers not
working of one is loaded more than the other. I don't quite
understand this. Anyone know why? At any rate, you could use 220
or 110 to run a DC supply. I was going to use 110 because I thought
the transformer would be easier to get. I could be wrong. Either
way I don't see any way to use any of the transformers in the
enclosure now. Search ebay for "toroid transformer cnc" and you
should find one for $60. There are TONS of big capacitors in the
enclosures to use. And the bridge rectifier should work perfectly
fine if you get a new transformer. Otherwise a Rectron 1000V PIV
35A bridge rectifier can be had from Mouser for less than $4.

Well, that's enough of a novel for now. I can send you a drawing of
how I intend to wire mine. If you give me maybe 2 weeks, I can send
you an AutoCAD file of the entire wiring diagram.

Kevin