# These motors are getting HOT! Why?!?



## macmikeman (Jan 23, 2007)

Check the phase converter output. A-B, B-C and A-C See if the readings are all good. Phase converters can jack you on the derived phase pretty easy. Derived to ground is useless to read by the way most of the time with Converters.


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## sparkiez (Aug 1, 2015)

macmikeman said:


> Check the phase converter output. A-B, B-C and A-C See if the readings are all good. Phase converters can jack you on the derived phase pretty easy. Derived to ground is useless to read by the way most of the time with Converters.


My voltage readings are phase to phase, not phase to ground.


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## wildleg (Apr 12, 2009)

you haven't given any information about the mechanical operation. did you check rotation, binding, etc on the output side ? (I'm assuming you did, but . . . . it wouldn't be the first time two motors were fighting each other)


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## just the cowboy (Sep 4, 2013)

Electronic phase convertors may be the issue. Not everything runs good on them. They do not produce a true third leg . 


Also do you have a picture of the hook up diagram for the motors, most use some type of jumper to do that change. If a wye wye motor don't use jumpers the horsepower usually changes, and your nameplate don't show that.


Do you have a small VFD around with single phase in three phase out, If so try running one motor off of that. Here is one for $136.00 https://www.automationdirect.com/ad...ol/gs1_drive_units_(120_-z-_230_vac)/gs1-21p0


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## John Valdes (May 17, 2007)

sparkiez said:


> Here is what I've done:
> 
> Confirm that the motors are wired for 230V
> 
> *Take an amp draw. On two of the motors I'm reading 0.* On one I'm ready .25. This is worrisome, but not the end-all. These motors are supposed to draw ~2A FLA, however they were drawing ~3A.



How long did they run on 460 before you realized the voltage was wrong?
O current with the motor running sounds to me like a high resistance connection somewhere.
Could even be inside the motor. Or motors.

Have you tried a new motor in place of the motors that show zero current draw?
Since you measured voltage at full load at the motor, I'm kinda leaning to the motor itself. And the only reason I say that is you say the motors were on 460. Or did you mean they were wired for 460 and you caught that before they were powered up?
Did you run these motors at 460 then change them to 230?


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## John Valdes (May 17, 2007)

Note. The two connections box diagrams look to be wired for 460 not 230. Delta.
I see no jumper to make the motor connection a star or wye. Star for high and delta for low voltage on IEC motors.


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## just the cowboy (Sep 4, 2013)

*wye/ wye wye*



John Valdes said:


> Note. The two connections box diagrams look to be wired for 460 not 230. Delta.
> I see no jumper to make the motor connection a star or wye. Star for high and delta for low voltage on IEC motors.



I said same thing about jumpers. But if you look at nameplate it is a wye /wye wye motor.


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## gpop (May 14, 2018)

Wiring looks wrong.

One y connection is inside the motor. When you made it a yy there should be one external y connection where all 3 leads are joined


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## gpop (May 14, 2018)

If you understand that the bolts on the ceramic block are not connected to anything underneath then you have to ask yourself why 3 wires go no where on the left side of the picture


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## sparkiez (Aug 1, 2015)

That is what I'm seeing also. To clarify:
The motors were at 460. I changed the wiring to 230V. I used the schematic provided with the motor. That schematic does not show there being a jumper for a 230V connection. I'm showing the wiring before I changed it and after.

Now in the past, I've wired these things for 480 and removed those jumpers. I suspect that this has happened here, or that the motors were originally shipped for 460V. I'm going to confirm, and then add the jumper in, as I suspect I'm only running on one set of windings. I'm also going to double check the wiring diagram on the peckerhead to see if that jumper is in fact shown there.


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## gpop (May 14, 2018)

If they are to be joined skip the jumper and just put all 3 on one bolt


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## JRaef (Mar 23, 2009)

I don't think you have it connected correctly.


Look at the diagram on pdf page 8 of this document. There is supposed to be a jumper across the terminals on the left side of your photo of the terminal block

https://download.sew-eurodrive.com/download/pdf/LC_en-US_2010DRConnectionDiagrams_9PD0058.pdf


Also, there is a brake on your motor, the brown and yellow wires that come off of the right side of your photo of the terminal block. It's possible that because they are feeding an internal rectifier to make DC for the brake, the fact that you are on a phase converter is making that rectifier not produce enough DC and the brake is not fully releasing.


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## JRaef (Mar 23, 2009)

Easier image to look at...


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## sparkiez (Aug 1, 2015)

I didn't know about the brake on the motor. However, the issue was that U2-V2-W2 were not connected. Glad it was something simple. I would much rather miss something simple than something complicated.


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## Forge Boyz (Nov 7, 2014)

Working on this style motor always makes me glad most of the ones I work with are NEMA.

Sent from my Moto Z (2) using Tapatalk


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## Cow (Jan 16, 2008)

Forge Boyz said:


> Working on this style motor always makes me glad most of the ones I work with are NEMA.
> 
> Sent from my Moto Z (2) using Tapatalk



I agree.


We come across these a few times a year. I always have to stare at them a bit longer than the usual Baldor, etc. I can almost wire those with my eyes closed.


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## gpop (May 14, 2018)

Forge Boyz said:


> Working on this style motor always makes me glad most of the ones I work with are NEMA.
> 
> Sent from my Moto Z (2) using Tapatalk


If you remove the ceramic block you can wire nut like a normal motor (most rewinds come back with out the block as they tend to crack easily) you just have to get use to the u-v-w markings.


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## Forge Boyz (Nov 7, 2014)

This reminds me of a panel saw I ran a circuit to. It had one of those motors on it, and was bought as a 230v 50hz saw, which obviously doesn't work. We asked about switching the motor to 480v so it could run on 60hz (and so we didn't have to set a transformer) and were told that one of their people had to do the conversion or no warranty.
I was there the same time the tech was doing the voltage conversion, and he seemed to be taking his good old time changing the motor starter. When he got to the motor, he took the peckerhead apart, and after a while when I walked past, he said "Hey can you make sure I'm doing this right. I've never changed the voltage on one of these before." [emoji38]

Sent from my Moto Z (2) using Tapatalk


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## micromind (Aug 11, 2007)

With U2, V2 and W2 disconnected, 3 of the 6 coils were not energized, leaving the other 3 to carry the entire load. 

Even though they were grossly overloaded, the line current would be somewhat normal but instead of being split among 2 sets of windings, only one set was carrying the total current. 

This would cause fairly rapid heating..........lol.


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## frenchelectrican (Mar 15, 2007)

That is double Y motor if you hooked up on 230 volt source.,, I have see that from time to time 

that what happened if you forgot to get second set of Y winding hooked up it will get hot pretty quick. 

If you ran on 460 volt then single Y will do it. ( some will use special jumper for this purpose )


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## Tonedeaf (Nov 26, 2012)

The motor are most likely too heavily mechanically loaded. you need to checks the belts or chains


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## birddog386 (Feb 6, 2018)

Sparkies, I’m sure you’ve checked, but are these motors sized correctly for the conveyor. For example, what are their Duty Cycle rating on the nameplate?


Sent from my iPhone using Tapatalk


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## splatz (May 23, 2015)

sparkiez said:


> When I checked out the motors, all motors were wired up for 460V. Given that we were on 240V delta, I changed them over to 230V. I've wired up many three phase motors, I'm sure they are correct, but I have included a picture here as well. I also 100% confirmed this matches the wiring diagram provided on the motors yesterday.


In my experience when you're certain like this, and especially if you say out loud "I am 100% sure about THIS," the universe will spank you for it.


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## birddog386 (Feb 6, 2018)

sparkiez said:


> That is what I'm seeing also. To clarify:
> The motors were at 460. I changed the wiring to 230V. I used the schematic provided with the motor. That schematic does not show there being a jumper for a 230V connection. I'm showing the wiring before I changed it and after.
> 
> Now in the past, I've wired these things for 480 and removed those jumpers. I suspect that this has happened here, or that the motors were originally shipped for 460V. I'm going to confirm, and then add the jumper in, as I suspect I'm only running on one set of windings. I'm also going to double check the wiring diagram on the peckerhead to see if that jumper is in fact shown there.




There must be a terminal link between T4, T5, and T6 for the 230vac (YY) connection. 


Sent from my iPhone using Tapatalk


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## JRaef (Mar 23, 2009)

Tonedeaf said:


> The motor are most likely too heavily mechanically loaded. you need to checks the belts or chains





birddog386 said:


> Sparkies, I’m sure you’ve checked, but are these motors sized correctly for the conveyor. For example, what are their Duty Cycle rating on the nameplate?
> 
> 
> Sent from my iPhone using Tapatalk





birddog386 said:


> There must be a terminal link between T4, T5, and T6 for the 230vac (YY) connection.
> 
> 
> Sent from my iPhone using Tapatalk


See post #15, he figured it out.


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## micromind (Aug 11, 2007)

splatz said:


> In my experience when you're certain like this, and especially if you say out loud "I am 100% sure about THIS," the universe will spank you for it.


Lol.....yep.......the more certain of anything I am, the greater the odds of me being wrong........


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## sparkiez (Aug 1, 2015)

splatz said:


> In my experience when you're certain like this, and especially if you say out loud "I am 100% sure about THIS," the universe will spank you for it.


Well, I'll take a spanking if that finds the problem. I mean, what else can you do when you look at something and don't see it? You get a new pair of eyes. I mean look at this image. It was so obvious I just overlooked it. The graphical diagrams kinda threw me too. I'm so used to a simple schematic.


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## splatz (May 23, 2015)

sparkiez said:


> Well, I'll take a spanking if that finds the problem. I mean, what else can you do when you look at something and don't see it?


THAT is the key, fixing it is much more important than ego, we all have to remind ourselves that periodically (or for some handsome devils, every fifteen minutes or so) :thumbsup:


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## HackWork (Oct 2, 2009)

splatz said:


> THAT is the key, fixing it is much more important than ego, we all have to remind ourselves that periodically (or for some handsome devils, every fifteen minutes or so) :thumbsup:


Are you talking to me?? You must be talking to me, I am by far the most handsome devil here.


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## splatz (May 23, 2015)

HackWork said:


> Are you talking to me?? You must be talking to me, I am by far the most handsome devil here.


Did you mention that? I hadn't noticed.


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## sparkiez (Aug 1, 2015)

splatz said:


> THAT is the key, fixing it is much more important than ego, we all have to remind ourselves that periodically (or for some handsome devils, every fifteen minutes or so) :thumbsup:


One of the first things I teach newbies when troubleshooting is that no one, no matter how long you have been doing this, is immune to this sort of thing. Everyone does it from time to time. There is never any shame in asking someone for help or seeing what you are missing. In fact, if you had to pick one single skill when performing most of this work that trumps all others, field-wide that would be to recognize when you need to take a step back and get more information through any means you have available to you. Nothing is more important. If you aren't sure, get sure.


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