PM932 Mill Motor Upgrade

I question if that is even a 1.5 hp motor. 6.8 amps single phase is in the 1hp range, a 1.5hp motor should be more in the 9 amp range. That would explain why you can’t find a 1.5hp motor in an IEC 80 frame at 1800 rpm.

I have a 1hp 3 phase motor on my Burke Millrite running on a VFD, it does just fine for 99% of what I need to do. The only time I am hp limited is when using large cutters at reduced speed. If I move the drive belt to the lower speed range, I don’t have a problem. You might be fine with a good quality 1hp motor on your mill. At least it will be easy to find and not custom.
 
Similarly to what I previously indicated, physically it is very unlikely that a true 1.5 or 2Hp 1750 RPM motor would fit in an 80L frame, as there is not enough room for the windings. It is not unusual for some Chinese motors to be overrated (Hp) for their size. I see only three options, go with a 1.0Hp 80L motor if you do not want to turn down the shaft, go with a 90L and turn down the shaft, or switch to a BLDC type of motor in an 80 frame size and add a speed controller. Motor availability is also an issue these days, I was helping another individual with a metric motor replacement and many vendors were out of stock of even common sizes.
 
Yep

Some of the problems with digging up an old thread and then folks sincerely wanting to help but maybe not reading carefully the details. I get that, know that the help comments are sincere. As stated before I've read all the different posts I could find regarding this subject and just hoped someone might respond if they had stumbled across a decent three phase replacement. I never said I had a 1.5"HP" motor. I am very well suited and capable of purchasing a 90 frame motor and turning the shaft... building adapter plates, etc. BUT Since there have been many past posts (even some in this current thread) that imply or say "Matt hooked me up...., ".... I got a three phase motor from Matt", "... QMT has three phase motors.... " etc, etc, etc...... I just wanted to make sure there wasn't a source out there that currently offered a drop in 3ph, metric 1.5KW motor. At my age I look for ways to "de-complicate" my life. I do sincerely appreciate all you fells trying help, and this has convinced me to move on and take the path of greater resistance. The 6.8A you referred to might have been from the photo of the plate on the first page of this thread. (That's not the tag from my motor) The motor I'm replacing has a nameplate current rating of 11 Amps so likely something close to 2HP. The listed frame is a 90L, but with a 19mm shaft I feel like this is not too common in this power range. At least that is what I've found so far. The actual measurements match that of the IEC 90, except for the small shaft. The reason I resurrected this old thread is because it was the one with those most discussion related to my dilemma.

Again,

Thanks :)
 
I didn’t pick up you were referring to a different issue, when you said in a previous post your current motor is 1.5, I assumed you meant HP like the original poster and not KW. A 90 frame 1800 rpm motor with a 19mm shaft does not meet IEC standards and is custom, so it is highly unlikely you will find one anywhere else than one of the machinery resellers. Since PM doesn’t have it, you could try Eisen since many of their machines come from the same factory as PM. You may have some luck with companies like Lafert and Brook Crompton that are heavily into metric motors.

I just had a thought, the 2hp motor on my 1236T has a 19mm shaft. You might be able to swap the end housing on one of those with your flanged one from the single phase motor if PM has one of those. That way you don’t have to deal with the larger key slot on the standard 90 frame motor.
 
@pbiYoung

Maybe the following site will be of help to you. I would almost bet that these are the folks that made your "customized" motor. You may already know all of these dimensions in which case this maybe a waste. Using the old string also confused me as I was searching for the motor model from the label posted at the start! Not necessarily yours? So with that in mind I spent time searching for you and the fruits of this are below. I had done this for you earlier and then got interrupted and did not post it until now.

I posted a picture of the motor plate on my PM940M-VS-CNC 1.5KW 3phase motor earlier. Model: YUBP90L-4 It also has a 90 frame, but now I am wondering if it has a 19 or 24mm shaft.

So anyway, I will go a head and post these links I found for you. Maybe there is something in there that is useful. GW ELECTRIC (SHANGHAI) CO., LTD. They have a link to send them email for inquiries. Ironically, one of my former students now lives in Shanghai.... a big place.

Go to: https://www.gwindustry.com/ and select induction motors. Then you can find and compare your motor and dimensions. via the URLs listed below.

https://www.gwindustry.com/product/ylj_series_single_phase_capacitor_start_and_capacitor_run_motors This will take you to a single phase motors including yours. There you can download a pdf descriptions and size specs at:

This file shows your motor to be a 90 frame and says it has a 24mm shaft, but the -19A on your motor label may mean the shaft size was custom. Measure it. Maybe this is a special made...

Also, here is their site for the 3 phase motors
www.gwindustry.com

GW IEC Metric YSJ Series Three-Phase Motors 　　　　　　　　　　　 　　　　　　　　　　　 　　　　　　　　　　　 - GW ELECTRIC

· IEC standard design. · High efficiency, IE-3 and China Efficiency Class 3 (GB18613-2020). · High q...
www.gwindustry.com www.gwindustry.com

and here is a listing of their induction motors:

Look at YSJ90L4H The 90 means frame size, 2.0HP/1.5KW and as Mark said the shaft is 24mm. While the 80 frame shows the 19mm shaft diameter the 90 frame size shows 24, I think it is quite possible that they have versions where the 90 frame has a 19mm shaft or maybe used to. It now might be a special order but maybe ..... I am not for sure what the H in the model number stands for.

I have tried a three phase YSJ90L4 with my Hitachi VFD and it ran fine at various speeds, but I had no load on the shaft. It was designed for 50Hz to yield 1400 rpm. So 60Hz should push it up to ~1700 rpm. Interestingly enough it has a 19mm shaft!

Dave L.
 
@Ischgl99
Now that's an idea worth looking into. Ill call them.
I also saw a bunch of motor flange mount end plates on eBay and had a similar thought for a moment but didn't pursue it. Now you've inspired me to take a look at the 90L motors and think about swapping the end plates. I have found quite a bit of 19mm shaft 2HP motors with conventional bases. If that doesn't work out then i take a new motor chuck it up in the lathe and "unconventionalize" it. Not my first choice and likely void the warranty, but what machinist has ever worried about a stinking warranty.
Thanks
 
Hopefully the end plates are similar enough that it works to switch them out.

If you do machine the shaft of a new motor, the key slot on the 24mm shaft is wider and goes down to a diameter of 16mm, so you will need to figure out what to do about that. I don’t think I would want to go deeper on the slot at the same width since 19mm is small enough for 2hp that the wider key slot at full depth may weaken the shaft enough that it doesn’t last. If you can find a motor with an unkeyed shaft that you can turn and put a new key slot in, that might be the better option.
 
@B2
B2 said:
Look at YSJ90L4H The 90 means frame size, 2.0HP/1.5KW and as Mark said the shaft is 24mm. While the 80 frame shows the 19mm shaft diameter the 90 frame size shows 24, I think it is quite possible that they have versions where the 90 frame has a 19mm shaft or maybe used to. It now might be a special order but maybe ..... I am not for sure what the H in the model number stands for.
Click to expand...
"used to" are the key words you used there-
Same motor as yours and yours likely has 19mm shaft too.... its a Custom motor. Here is the plate from mine. Its a 90 size frame motor with a 19mm shaft.
.....and yes I have learned my lesson about digging up old threads :grin big:


IMG_E0318sm.jpg



Thanks
 
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That is certainly an option. The only difficult part looks to be the blind broach for the keyway. I haven’t done one of those, so don’t know what is needed for that. There are a couple bearing seats that would need to be machined fairly accurately, but overall it doesn’t look too bad to make a new one. The limiting factor is the bearing on the upper portion limits the size of the shaft, so boring out the existing one is probably the better option.

The bearing that fits on the top part of the stub shaft is 35mm ID, with an IEC 90 motor, it uses an 8mm keyway, so that only gives you a couple mm wall thickness at the keyway, which is probably not enough. It might last for a while, but I would be concerned about it cracking over time. A NEMA 143 motor has a shaft diameter of 7/8”, which is 22.22, so gives you a bit more wall thickness, but you lose some shaft engagement since you would need to make an adapter plate that would raise the motor up a bit, assuming you are using the existing shaft and just boring it larger. The plus of that is the NEMA motor shaft is a bit longer than an IEC motor, so if you designed the plate right, you wouldn’t loose much shaft engagement in the stub shaft. If you made a new stub shaft as well, that would not be an issue since you could make it as long as needed. The keyway in the 143 motor frame size is actually smaller than what is in there now, so you could modify it as needed.

It’s frustrating they are using old standards for the motors in these designs, it would be nice if they were off the shelf IEC sizes. They’re made in China and Taiwan, they’re not going to be NEMA unfortunately. I have the same problem with my lathe, if I wanted to upgrade the motor to something of a higher quality, it would require some modifications since it is not a standard design. Motor sizing has changed over the years, so these were probably designed to an old standard and never updated to an off the shelf design.
 
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