3 phase 220VAC motor not running properly on 208 3 phase

[team08]

I am having problems at my shop with a new to me clicker press (hydraulic press for die cutting). The seller assures me that the machine worked perfectly at their shop, but it does not seem to work correctly in my shop. Basically, the motor spins up fine (yes in the correct direction), but when I go to activate the press, it is really weak. I can barely punch through paper with a small die. I did keep a meter on the line to see if there is any droop in voltage, but it is rock solid at 208.

This is the second machine we tried with the same symptoms. The plate on the motor reads 220VAC 3 phase 60Hz, 1HP. I thought that there was a magical 10% rule on this type of motor so that they would operate from 200-240VAC? Any suggestions on options? The way I see it, I can either call the power company and see what my options are for getting 220 ($$$$ I am sure), or maybe a transformer setup. I called Grainger about it and they recommended PN 1H271, and two of them. How would this work? Wouldn't I need one on each leg? Thanks for any help!

 

[ScottyUK]

skogs,

Harsh but true. That really does look rough.


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If we learn from our mistakes I'm getting a great education!

 

[jraef]

Ouch Gunnar...

Team08,
I would say that if you paid for it, you probably paid too much and you should try to return it. If it was thrown in for free, it might be salvageable. But from the looks of it, this thing has been to a rewinder and messed with, so the only way to tell for sure what you have is to take it to one again, which is not likely worth the time and money for a 1HP motor. A used one will likely cost you less.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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[waross]

And did anyone notice the 318 550 60HZ stamped on the side of the connection box?
team08, if you decide what voltage to try, I can suggest a transformer connection.
A 240:48V transformer will give you about 250V if fed from 208V.
Probably the closest size will be 250VA.
The 48V winding will have to support full motor current.
That gives 48V x 3.8A = 182.4VA
Check the price and availability on two 250VA transformers and let me know if you want to continue.
BTW today I was hooking up a 112KVA open delta, autotransformer buck transformer to power a group of 480V fans on 600V.

Bill
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"Why not the best?"
Jimmy Carter

 

[ScottyUK]

Yeah, I noticed the 550V and couldn't make my mind up about the other marking. It would equate to a motor rated at 460V / 50Hz, which is a weird combination: a standard voltage from the 60Hz world, on a 50Hz motor. I can't find anywhere in the 50Hz world where 460V is a standard voltage, certainly not Italy where this motor originated.

Personally I'd buy a replacement motor from a recognised brand off ebay and dump this mutant motor in the skip or weigh it at the scrap yard. In that size range they're common as dirt and almost as cheap.


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If we learn from our mistakes I'm getting a great education!

 

[waross]

The Grainger transformers will get you up to 229V. I see that the Grainger models are rated "Buck-Boost" which I forgot to mention. Fairly important.
If you are happy with 229V use the Grainger transformers. No guarantee.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[waross]

A pair of Grainger 1H272 will give you 236V.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[OperaHouse]

I would think you could pick up a good used motor of that frame cheaper than new transformers. You don't know what you have and neither does the person who sold it to you. I've seen motor plates like that even on new equipment. Reading motor current with a clamp on meter might give you some idea what voltage the motor is. I would just switch motors rather than hang a bunch of junk on.

 

[macmckim]

Based on the nameplate the motor is an IEC frame 80 B5, meaning round body with B5 (similar to Nema D-flange)
If you are in N.A., there are number of companies that offer replacement. IE: Baldor MVM5550D.

The existing motor really need to be check out, you have no idea of its past life. Remove the motor, find a motor shop
and get estimate (overhall or repair) and cost on a replacement. Then you have a motor that will run for years.
Also use a good cable-conduit connector too.

 

[team08]

Unfortunately, I don't think I can just buy a standard motor since it looks like the odd casting is part of the motor. You can see it better in this picture. So maybe I just need to buy some transformers and use it as is for now until the motor dies. The one other thing I am wondering is perhaps the lower voltage affects the control logic?

Waross, can you give me a hand with what I will need for the transformers? I have 4 wire 208, but I think the neutral/ground wire is only used to ground the frame. Not sure if this affects the need for 2 or 3 transformers? Thanks again guys!

 

[edison123]

Without even knowing what the motor voltage is, how would you spec the transformers, which incidentally, are additional components to maintain /that fail and come at a cost.

As others have said here, either buy a new motor matching your requirement or rewind this motor for the right voltage, speed and frequency in a good motor repair shop.

 

[waross]

Ty this link. You probably need diagram B1.
The points to bring out are H1, H-X, and X4.
Connect both H1's to "A"phase.
Connect one H-X to "B" phase and the other H-X to "C" phase.
Poweer the motor from "A" phase, one X4 and the other X4.
Or, use diagram G1, boosting.
I'm very tired today, so if someone challenges my information I'll take another look.
To calculate voltages, first add the primary voltage (240V and the secondary voltage (24V, 36V or 48V).
For example, 240V + 36V = 276V, but we will be feeding 208 rather than 240 so use 208V/240V for a developed voltage of 239.2V.

Bill
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"Why not the best?"
Jimmy Carter

 

[LionelHutz]

Is there not a split between the motor and that casting it's attached to? We still can't see from the picture how exactly it's build. According to an earlier poster it is a standard IEC flange motor meaning it should be bolted onto that casting.

It that casting actually is part of the motor (custom cast drive-end endbell?) yet the rest of the motor is a standard frame size then maybe you could just use the stator of a new motor. You could also use the rotor of a standard frame motor if the rotor has the same shaft end. Piece something together to get the right voltage and a motor you know will work.

Read the third response from itsmoked describing the hydraulic press that was run for years at the wrong voltage. Just imagine how annoying that has been for the operators and how much production time has been lost with it that way. All because the people involved just accepted that's how it was instead of looking into it and getting it working correctly.

I wish you luck with the autotransformers because from your description on how weak the motor is I don't think an extra 40V is going to make it work significantly better. The motor should be running at 70% power. If it was just lacking a little power than maybe...

 

[team08]

I did put on a clamp meter and read ~3.3A on each leg so it seems to be in spec of what the butchered motor plate says. Maybe the logic in the controller is faulty at the lower 208? I wish I could just try a transformer to see if that solves the problem. At this point I am not convinced that a new motor will solve the problem either. I am at a loss, guess it is time to have it out with the seller. I will let you know how it pans out!

 

[Compositepro]

A Clicker Press has hydraulic load and limit adjustments. Have you ruled out all hydraulic problems?