Tips/Techniques Motor Conversion question

Tips/Techniques

Tomc938

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Does anyone know what this would need to run on 220, or if it would be even possible? I don't have 3 ph either.

It's on a Bridgeport mill.

Thanks!

Tom
Screenshot 2023-09-02 at 8.47.59 PM.png
 

YotaBota

Mike
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Tomc938

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Give these guys a call and send them the data plate to confirm the correct VFD.

Do you know if the motor is wired 220v?
Thanks for the link.

Checking on the wiring.
 

Dabbler

ersatz engineer
It looks pretty straightforward. Wire the motor for "low volts", and use a 1 HP VFD. Program it for Vector control, and 3 amps motor current. The TECO support staff will give you the necessary settings.
 

DavidR8

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Conveniently you could run that off 120v with a 120–>240v vfd.
Teco makes one. I used one for my surface grinder.
 

Susquatch

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I like that the voltage winding configuration info is right on the nameplate. Sometimes the numbers on the wires are hard to read though. If they are not obvious when you open the connector box, look carefully at each wire - sometimes it is pressed into the wire insulation. Sometimes you can only see one side but the pairing identifies its mate. Patience, a magnifying glass, and a strong light are your friends. I usually put new labels on them to avoid future confusion.
 

Susquatch

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This will not do vector mode sadly

I think for many applications, this doesn't really matter. The difference between regular inverter mode and sensorless vector mode is absolutely amazing on a big motor, and I wouldn't want to be without it on a mill or a lathe. But I doubt it would really matter much on a small pump motor.

But this is really just an opinion cuz I've never actually tried it on a small motor.
 

Dabbler

ersatz engineer
Sice the motor is 1/6 HP, it is far easier to be replaced, even if a custom flange/adapted needs to be fabricated. A VFD is a costly route compared with buying a used 1/4HP 220V/110V motor, and far too complicated.

Interesting thought about not having a SV mode on small motors. Proplly work, but not a great option. SV really changed the game. I wouldn't want to go back.
 

Dabbler

ersatz engineer
If you’re just running at 60Hz and not too concerned with the actual motor rpm is SV of any advantage?
I think it would work, just like VFDs before SV. But they were finicky about motor start and heating issues. The SV measures back EMF and adjusts the effective current accordingly. If you lower the average current too much, the motor has starting problems.
 
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Tomc938

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To everyone who gave their advice - thanks!

Unfortunately, while the ad was still up last I looked, the seller is not responding to my emails. Must be sick/dead or sold.
 
To everyone who gave their advice - thanks!

Unfortunately, while the ad was still up last I looked, the seller is not responding to my emails. Must be sick/dead or sold.
It's also a long weekend, so they might be out having fun in a ferry lineup or at the airport..... Give 'em a little time, 'tis the last weekend of the summer season, all hope is not yet lost......:cool:
 

Mcgyver

Ultra Member
On using a VFD on a mill..... one of the nice advantages of three phase is you can switch from forward to reverse and not really hurt anything. i.e. power tapping, switch from forward to off but its still getting close to bottoming out, so just turn the switch to reverse and away you go. It can be handy, I do this frequently when power tapping. The mill is powered by a RPC. I have numerous VFD setups but this mill is the one I have the need to go from forward to reverse with and its not on a VFD.

So....curious, is that just fine with a VFD or a big a nono? I'd guess the later, but curious if anyone knows?
 

Susquatch

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So....curious, is that just fine with a VFD or a big a nono? I'd guess the later, but curious if anyone knows?

Do it all the time. Works just fine. Very smooth transition from full one way to full the other way is easily done. Because the rates can be programmed in, you can configure it to be as smooth as you like.

I do not power tap though. So I suppose the transition from one direction to the other might not be as fast as desired for that kind of application. I'd have to change my rates to see how fast it could go. But I don't see any reason off the top of my head why it couldn't be just as fast. But I don't know that for sure.

Basically, I like the slower smoother startup and stops. It's much easier on everything. Can't wait to get it going on my lathe.
 

thestelster

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On using a VFD on a mill..... one of the nice advantages of three phase is you can switch from forward to reverse and not really hurt anything. i.e. power tapping, switch from forward to off but its still getting close to bottoming out, so just turn the switch to reverse and away you go. It can be handy, I do this frequently when power tapping. The mill is powered by a RPC. I have numerous VFD setups but this mill is the one I have the need to go from forward to reverse with and its not on a VFD.

So....curious, is that just fine with a VFD or a big a nono? I'd guess the later, but curious if anyone knows?
I have a VFD for my lathe and mill. I will forward and reverse often when power tapping on the mill or doing metric threads on the lathe. Never had a problem (10 years now with VFD's). And now that I have braking resistors on both machines, I can stop in under a second. I do have drum swithes on both machines, so a flip of the lever swithes directions lickity split!
 

Susquatch

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I do have drum swithes on both machines, so a flip of the lever swithes directions lickity split!

This is not intuitive to me. I wouldn't have thought to even try it. It will take me a while to sift through the nuances. But I have a few questions that scream at me.

1. Since the VFD doesn't know you have a drum switch (which basically swaps two phases on the output side of the VFD), does doing that bypass the accell decell rate curves? If so, it might serve as a great way to do stuff like power tapping!

2. Since the VFD doesn't know you have a drum switch, does doing so drive the sensing electronics bonkers???

3. Does that work in SLV mode too? If so, what a nightmare it must have been for the programmers! Everything humming along maintaining rpm with just the perfect voltage, current, and back emf, and then in a millisecond.... Holy crap, the inputs just screamed that we are 270 degrees out of phase! Houston, we have a problem. EJECT!

Maybe I'm over thinking this...... But it just seems to me that reversing using the VFD inputs creates a much smoother controlled transition.

I'm also thinking that might not be a universal VFD feature. Some VFD makes might fry doing that.
 
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