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3 phase motor and VFD questions

I scrapped my GE washing machine. Actually, it scrapped itself when the drum spider broke making repair too expensive to consider. But now I have what appears to be a nice 3 phase motor. The specs are ambiguous. The voltage is listed as variable. The frequencey is listed as variable. The amperage is listed as 2.5 amps. So at least there's that. It is quite heavy. Since I removed all the electronics and the wiring harness I am going to try to get the motor to run on the bench and then measure the voltages at different speeds. I have a pretty nice DVM but I don't know how well it will measure AC voltage at frequencies much above 60 Hz. The meter will measure AC frequency. But I'm guessing that the output from the washing machine VFD is probably pretty far from a good sine wave. The VFD is a pretty simple bare bones unit. Anybody know? I do have a VFD that takes 120 volt single phase input and outputs

230 volts at up to 400 Hz. I would like to run the motor from it if I can but what if the voltage is too high? Can the motor be run at too high voltage for a while without damage? Will too high voltage just cause overheating? Since the motor is VFD rated the insulation must be pretty good so I'm thinking too high voltage is probably OK for at least a few minutes. If I can suss out what the original GE VFD expects for signals from the washing machine control and am able to copy them I will do that. But If I can't then I will want to try another VFD that I know how to control. There are at least two reasons I want to re-use this motor. One is that I hate to throw out good stuff. It pisses me off to waste stuff. Another reason to re-use the motor is that it is a high quality motor. The way it was used in the washer to drive the drum required high quality bearings and general high quality robust construction. The drive belt tension was extremely high so this put a very high side load on the front motor bearing and a high side load on the rear bearing. The motor bearings still feel great and will probably last forever. I'm thinking that with the proper reduction the motor would make a great motor for a small lathe and my son has a 9 inch South Bend that would be much easier to use if it had infinite speed control. Thanks, Eric
Reply to
etpm
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Did the washer run on 120 or 240? You should have saved the motor control board and the necessary parts of the harness.

The voltage and frequency aren't ambiguous, since the drive voltage has to change with the frequency.

Reply to
Michael Terrell

Do you even read what you reply to?

--
"I am a river to my people." 
Jeff-1.0 
WA6FWi 
http:foxsmercantile.com
Reply to
Fox's Mercantile

te:

should have saved the motor control

Do you ever have a day without PMS? He said his VFD. He gave no information on the one that came with the motor, or if it was in good condition. His s tatement of 'trying to get it working' is rather vague. It may or may not o perate like the stand alone VFD.

I was hoping to get more information out of him, but all you do is bitch. I f he can get it to run from the existing drive, yes he can measure the freq uency and voltage. From there, he can determine if his 120V VFD can be prog rammed for his needs.

VFDs aren't that complicated, but a lot of idiots can mess them up. I had t o repair a pipe bender at a local Art Canopy factory. They had just moved, and hired a contractor to wire up their machinery. The idiot wired the 208/

240 Volt machine to a single 120V circuit. You could stop the thing with yo ur finger.

I made the idiot install the right breaker, then I added a boost transforme r to run it off 240 to 245 volts. It ran twice as fast as it had, on 208V.

Aren't you supposed to be working on your latest plans to catch that #$%Z^7 Road Runner? :)

Reply to
Michael Terrell

And all you do, as usual, is act like an asshole, then make the posting about you and how clever you are and how stupid everyone else is.

--
"I am a river to my people." 
Jeff-1.0 
WA6FWi 
http:foxsmercantile.com
Reply to
Fox's Mercantile

(...)

Most VFD's can be jumpered for either 120 or 240VAC. Maker and model number would be helpful here.

If the voltage is too high, you'll burn up either the VFD, motor, or both.

No. You'll burn up the motor or burn up the VFD from too much current.

Yes. You will rapidly begin sweating profusely as the motor begins performing a rapid self-disassembly.

Washing machine motors are usually 1/2 or 3/4 horsepower. The South Bend 9" light duty (10K) lathe will suffice with a 3/4 hp motor. The

9" heavy duty flavor (10L) lathe might need a 1 hp motor. Bigger is always better: I'm not sure about the RPM but you should be able to extract it from the existing motor's nameplate. More: etc. Lots more on SB lathe motors, etc found with Google.

You'll probably also need a spindle speed tachometer. Something like this:

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558
Reply to
Jeff Liebermann
3-phase motor on a washing machine? Must be an industrial device, not hardly an over-the-counter consumer device.

With that in mind, you will need a simple 3-phase VFD, as a single device. They may be had with little fuss and at a reasonable cost. Such as:

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Only one of many options.

Do check that the motor is well-and-truly 3-phase, however.

Peter Wieck Melrose Park, PA

Reply to
peterwieck33

I'll need to check my VFD to see if it can be jumpered to output

120 volts. I couldn't remember if more voltage would cause more current. Thanks. Since my son is doing light duty work with the lathe 1/2 HP should be fine. And the motor he is using now is 1/2 hp. It's just a standard single phase induction motor though. The washing machine motor has a tach so that's covered. If I can get the existing VFD to work out of the washer. Cheers, Eric
Reply to
etpm

As I stated in my post I do have already a VFD that would work except that I think it only outputs 120 volts. And the motor nameplate says on it that it is a 3 phase induction motor. The voltage and frequency are listed as being variable. But Jeff L. suggested that it may be jumperable so I will need to check the manual. I didn't even think it may be able to output 120 volts. Cheers, Eric

Reply to
etpm

dly an over-the-counter consumer device.

. They may be had with little fuss and at a reasonable cost. Such as:

6XmkxxoCZ6kQAvD_BwE

So called 'High efficiency' washers have them, and so do some window Air co nditioners. They eliminate the need for a fancy gearbox and they can revers e direction easily. A smaller motor can be used in some cases. Variable spe ed is used to reduce energy use on smaller loads.

Reply to
Michael Terrell

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Peter Wieck Melrose Park, PA

Reply to
peterwieck33

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