# Motor Maintenance Schedule



## Mr.Awesome (Nov 27, 2015)

Hey dudes,

So as stated in previous threads, my motor experience has been zilch. Google says a lot of things but I wanted to reach out to guys here that work in the industrial sector for their opinions.

I work for a commercial property management company and we only have a handful of 30/40 horse motors running air handling units but I would like to try and start a regular maintenance schedule for them.
My question to the plant guys, is do you have such schedules and what all do you perform at what intervals?
Do you have a good reference for the type of bearing grease I should be using and how often they should be greased?
Do you megger out windings/feeders regularly? I see reference to "a stitch in time" on this site, I will check it out to get a grasp on what I should see with such readings.
Do you ever blow them down with compressed air/nitrogen?

Currently, we change belts annually. Nothing more. I would like to add on to this to extend their life. VFD maintenance would also be appreciated but for now my concern is with the motors themselves.
Thanks!


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## Moonshot180 (Apr 1, 2012)

SRI-2 grease is preferred, but you must know what type of grease is already packed in. Very important. Re-grease every 143 weeks.

For bearings, on motors 200 hp and less, replace bearings every 16 years.

Also bridge and megger every 143 weeks.


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## Moonshot180 (Apr 1, 2012)

Also, bridge readings should be balanced, any devitaion greater than 5% should be investigated.

for 480V motors, we insulation resistance test at 500VDC. Also important to factor in relative humidity. Humid enviornments can cause your PI polarization index test to fail.


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## Mr.Awesome (Nov 27, 2015)

Thank you Moonshot.
I will have to do some digging to figure out what type of grease is already in these motors, but thats good to know I can fall back on this SRI-2.
I'm not familiar with the term "bridging". These are wye connected motors, T1 2 3 poking out. Are you referring to simply meggering out T1 - T2 etc.?
Humidity will definitely be an issue some days. There is nearby ductwork bringing in untreated fresh air into the penthouse. I will flat out say I have no idea what a polarization index is but will look it up.
600V motors so I want the 1000V setting correct? Equal to or greater than the motor rating? Same with the rated voltage of the feeders?


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## Moonshot180 (Apr 1, 2012)

A bridge test is just a fancy way of saying you are going to measure the resistance of each phase winding, and also measure resistance to ensure there are no open windings in the motor. You want to be sure each phase is balanced, and that there are no open circuits, or failed windings..if this is the case, your megger/insulation resistance tests will not be factual.

I am not familiar with 600volt motors, only motors we deal with are 120vac, 480, and then up to medium votlage motors, 6.9kV synchornous and induction type.

For PI test, you megger the motor continuously for 10 mintues, then you calculate the 10 minute, divided by the one minute reading. You want the end resulting number to be greater than, or equal to two. Typically, motors that are rated less than 200 hp, and not form wound, don't require PI tests.

For the grease, SRI-2 is usually a dark green to blue color. Definitely don't want to mix grease types, this will cause bearing failure.

Do you have a copy of "A Stitch in Time"? that is a good publication that has a lot of great information.


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## Wirenuting (Sep 12, 2010)

Here is the Baldor guide that’s lists greasing intervals..

http://www.baldor.com/mvc/DownloadCenter/Files/MN416


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## Mr.Awesome (Nov 27, 2015)

Thank you gentlemen.
Moon,
I get why you are saying I can't test individual windings, but even if I'm passing through several windings I should still get similar readings between all leads should I not?
Someone can feel free to jump in an correct me if I'm wrong here, but up here I've gathered we simply run 600V commonly while you run 480V commonly. Not much difference in concept and design. (Similarly my buildings run 347V lighting vs. 277V)

I don't have a copy of Stitch but have seen links and references to it on the site. I will definitely give it a read.


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## Moonshot180 (Apr 1, 2012)

you want to read T1-T2, T2-T3, T1-T3, to ensure all motor windings are connected together and that they have balanced readings.

If all that checks out, then you can just pick any motor lead to megger from. One lead from your megger to any of the motor leads, and the other to a good earth ground.


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## Mr.Awesome (Nov 27, 2015)

Sweet we are on the same page. Thanks!

Only other question I haven't had answered yet...
Largely due to the outdoor air pumping into the penthouse, everything gets grubby over time. Is it worth it to blow out the motors or is there too much risk of driving debris into the windings?


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## Moonshot180 (Apr 1, 2012)

what are the frame size/types of the motors? For smaller hp motors, there may be no vents, may have T drains, but no open vents to allow dust or moisture in. Now the end bell on the non drive end may have a fan blade attached for cooling, but that itsn't drawing any outside air into the rotor, or motor windings. I would say you could clean that out from time to time if it gets nasty.


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## Mr.Awesome (Nov 27, 2015)

I can't answer the frame type etc. offhand, would need to go take a look at them.
But there are definitely vents. You can see windings inside and one even has a "exhaust" vent on it spitting out warm air.
I usually take a shop vac and brush to suck up the surface dirt when I've done the belts but I'm hesitant to actually try and spray out the vents.


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## MechanicalDVR (Dec 29, 2007)

Start and keep a log that lists each motor and what your readings are and what has been done.

https://www.carbontrust.com/media/147021/j7965_ctl154_motors_check_list_aw.pdf


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## Moonshot180 (Apr 1, 2012)

Oh if there are vents, and you are just wanting to clean up the outside..then yea, vac and clean vents with lint free rag, soak the rag in propanol also. Can you remove the vents? Some of our motors, the vents can be removed, then we take em back to the shop to give them a good cleaning, using propanol and sometimes, a pressure washer (for the motors with bigger screens that get oil, dirt and grit built up on them).


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## Moonshot180 (Apr 1, 2012)

MechanicalDVR said:


> Start and keep a log that lists each motor and what your readings are and what has been done.
> 
> https://www.carbontrust.com/media/147021/j7965_ctl154_motors_check_list_aw.pdf


 
Yes Sir. That is what we do. Have an extensive preventative maintenance program, we are always doing some type of PM on our motors.

This week we are having one of our 6.9kV Synchronous motors refurbished..


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## MechanicalDVR (Dec 29, 2007)

Moonshot180 said:


> Yes Sir. That is what we do. Have an extensive preventative maintenance program, we are always doing some type of PM on our motors.
> 
> This week we are having one of our 6.9kV Synchronous motors refurbished..


Done it that way for years and could easily tell when something was changing and get the drop on a coming problem.


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## Mr.Awesome (Nov 27, 2015)

Thanks again for the resources guys. Much appreciated since I'm starting from scratch on a subject I'm not versed in.

Mech,
That guide mentions thermal imaging. We have a Flir cam that was purchased to scope out leaky roofs. My company is putting me through imaging training this spring so I will be doing imaging on all motors, mccs, loadcenters etc. annually too.


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## just the cowboy (Sep 4, 2013)

*disconnect first*



Moonshot180 said:


> you want to read T1-T2, T2-T3, T1-T3, to ensure all motor windings are connected together and that they have balanced readings.
> 
> If all that checks out, then you can just pick any motor lead to megger from. One lead from your megger to any of the motor leads, and the other to a good earth ground.


OP you mentioned VFD's make sure they are disconnected first before meggering.


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## John Valdes (May 17, 2007)

I think one of the very best ways to predict and or catch motor failures is with vibration analysis.
A base line is confirmed and subsequent/routine tests are viewed with these numbers in mind.
Mechanical failure in many instances is the root cause of many motor failures.

Remember, less grease is better than more grease. In the motor shop we found that over greasing was a much bigger problem than under greasing.
Using the same grease as is present in the motor is important as well.

Blowing out AC and DC motors is sometimes discussed in the negative. I always used compressed air. Motor windings are varnished/epoxied and forcing foreign matter into them would not be easy.
Besides, compressed air is easy and effective.

All motors on VFD's should be looked at for proper cooling.
Knowing the actual turn down ratio is very important to motor cooling. When in doubt contact your motor shop or motor manufacturer.
Also motor catalogs have an enormous amount of information posted in them that most people ignore. Take a look through the first few pages of any motor catalog and see how much information they actually do provide.

One thing I saw a lot of during my career was the lack of back up equipment such as motors.
We did what was called a motor survey (I hated doing them) in facilities that listed every motor and exactly what it was and where it went.
We then proposed a back up plan for critical equipment.

In most cases the customer was hesitant to purchase back up equipment and we fully understood the monetary commitment.
But in most all emergency situations (personally if I see no doctors or nurses and no blood its not an emergency) the customer will buy a new motor as they need it right away and cannot wait for the repair.

You should have a close relationship with your local motor shop and in turn you will know your manufacturer.
Here, is this relationship, training and technical assistance can be achieved in many cases at no charge.


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## Mr.Awesome (Nov 27, 2015)

cowboy,
Absolutely. Disconnect and cap off the other end of whatever I'm clipping the megger to.

John,
Thank you also. While I don't have a ton of motor experience I have seen a pooched motor roll into my previous company's shop with windings full of grease. Less is better.
I never considered the varnish on the windings. My concern with compressed air was the small amounts of water in it, hence why I asked about nitrogen. If I start seeing a buildup inside maybe I will try squirting it out a bit.
I have a lot of research to do on these motors in general. This is new to me so I have some time to put in reading and gathering info, then utilizing said info.
The idea of a backup plan is where this idea sprung from. We lost a motor on our main air handling unit for an 11 story office tower a little while ago. There was a bit of panic as nobody ever thought of "hey what should we do if this happens". We are not a plant so there isn't as much worry, but we rely on that unit to warm up the building in -30C weather. Luckily one of the local shops had a replacement on their shelf and we had less than 24hrs down time. Hard lesson, but now I'd like to implement PM and perhaps keep spares sitting nearby on pallets.


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## Wirenuting (Sep 12, 2010)

We do a lot of air handler motors here. More then I care to think about. 
Over greasing is a killer and not cleaning air handler bearings shortens their life also. 

We will vacuum the big dust bunnies from the motors and use compressed air to blow them out if needed. Moisture isnt a problem for us as we use the buildings control air compressors and they have air driers, water oil separators also. When needed we will use a portable one with an oil/water separator on it. Remember it doesn’t take much air pressure to clear the dust. 

Motor and squirrel cage shives always get looked at and replaced when needed. We keep a spare set of belts at the unit. We do the preventive maintance on a schelduled basis year round. We can tell what units aren’t checked and what units will soon die. 

We have had a supplier “train” several of our bosses and workers on when to regrease a motor. They claimed motors should never be greased. You can guess the life span of those units. We have also had employees use powered greasers to lube motors, one tube per motor per month. Yup, short life span again. 

Most motor maintance should be based on size, usage and operating environment. 
Having spares is important for critical operations. 
Having access to a good motor shop will be your lifeline when things go bad. 

I figure if a newer motor less then 15hp lasts more then 10’years, you made your 
money on them. Older motors seemed to last forever but the preventive maintance was greater back then. Preventive maintance money is always the first thing to go. It’s a run to destruction kind of model these past 8 years.


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## Mr.Awesome (Nov 27, 2015)

They way you operate sounds exactly like what I'm envisioning. We only have a half dozen motors worth the effort so PM funds isn't a problem.


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## John Valdes (May 17, 2007)

Mr.Awesome said:


> cowboy,
> Absolutely. Disconnect and cap off the other end of whatever I'm clipping the megger to.
> 
> John,
> ...


Before I aim an air hose at anything, I aim it at the floor and squeeze the trigger to be certain there is no water present.
Do you know that in motor shops they pressure wash the windings with water and detergent?
Then they dry them. 
Since there was a motor on the shelf for this one, you can count on it being a standard frame motor and move on to the others.



Mr.Awesome said:


> They way you operate sounds exactly like what I'm envisioning. We only have a half dozen motors worth the effort so PM funds isn't a problem.


Now you have 5 motors to check out. Write down the name plate information from each one and open up a motor catalog.
If the frames are coming with the same HP and RPM and are listed in the catalog, these motors are readily available.
But I would find out which motors are stocked at the supplier so you know for sure. 
Motors cross by frame, rpm, voltage ect.... Manufacturer model numbers mean little if these are NEMA motors and IEC motors.
Good motor shops will stock both. 

Where you need to be careful is with special motors. Motors on frames that don't match the standard. D-flange? C-Flange? Special shaft?
Missing model #'s ect......
These are the ones to plan ahead on. When they go down there will be no motor in the shop to buy and maybe the only place you can get it is from the OEM. 
Learn how frame sizes work and how the dimensions are observed.
Look at any frame chart and see the numbers. Look at the illustrations to know where the numbers "measurements" are made.

With 6 motors in total, this should be a easy learning experience. Good luck.

Oh....I saw many motors come in packed with grease as well. Many had sealed bearings in them.
Make sure your motor shop or you remove the zirk fittings after installing sealed bearings. Then plug the holes.


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## micromind (Aug 11, 2007)

In my experience, the most common motor failure is using the wrong type of grease. 

A lot of motors come from the factory with either Shell Dollium of Mobil Polyrex. If you use any other type of grease with either one, you'll wind up with a gooey sticky mess that doesn't lubricate anything. The bearings will overheat and if not properly protected, the motor will burn up. 

The second most common failure is using too much grease, even if it's the right type. Motor bearings take surprisingly little grease. It's very tempting to pump a bunch in because that's somehow better. The actual reality is that too much grease will fly out of the bearings and coat the end-turns of the windings. This will cause premature failure. 

Even a little too much will cause the bearings to overheat and spew the now-liquid grease all over the inside of the motor. Seen it many times. 

There is a specific procedure to greasing a motor and if followed, the net result will be many years of bearing life.


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## Mr.Awesome (Nov 27, 2015)

john,
I believe you 100% but pressure washing motors sounds insane!

It just dawned on me that Moonshot's call for greasing every 143 weeks is every 3 years-ish. I figured this would be a once or twice a year thing.
Funny story about greasing procedure...
The bearings on one of our huge fans were squealing a bit and I found a note on the unit made up years ago by one of the old maintenance guys calling for "x ml" of grease. Not knowing how much was dispensing out of our grease gun, I brought in a little medicine cup and found out a half squeeze was "x ml".


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## Moonshot180 (Apr 1, 2012)

yep, and that is for motors that have to perform critcal functions in a nuclear plant, we have thousands of motors in our PM program, and we are literally performing re-greasing, PMs every week..

when re-greasing, we first make sure the motor has been in service, so the grease is still warm, then take out the drain plug, and apply X number of strokes to NDE and DE..then 2 hr run, w drain plug removed, to allow any excess drain. then re-install drain plugs.

Lately we have been replacing the drain plugs with grease relief valves, so after re-greasing, you are done.


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## Wirenuting (Sep 12, 2010)

Moonshot180 said:


> Lately we have been replacing the drain plugs with grease relief valves, so after re-greasing, you are done.


I started doing that years ago, it slowed the over greasing being done by some around here. 
The only other real problem we have is the remote grease fittings. The lines would wear thru in spots that couldn’t be easily seen. I’m the kind of person that wants to see the bearing I’m greasing. I hate finding a large dog pile hidden behind a squirrel cage.


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## Moonshot180 (Apr 1, 2012)

Wirenuting said:


> I started doing that years ago, it slowed the over greasing being done by some around here.
> The only other real problem we have is the remote grease fittings. The lines would wear thru in spots that couldn’t be easily seen. I’m the kind of person that wants to see the bearing I’m greasing. I hate finding a large dog pile hidden behind a squirrel cage.


 
I understand. Those piping lines can really get clogged up. If we are greasing a motor that is within a duct, and it has greasing ports on the outside of the duct, we will run a zip tie, or something of the sort thru the lines to be sure there isn't any old grease blocking the grease and drain lines.


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## Wirenuting (Sep 12, 2010)

Moonshot180 said:


> I understand. Those piping lines can really get clogged up. If we are greasing a motor that is within a duct, and it has greasing ports on the outside of the duct, we will run a zip tie, or something of the sort thru the lines to be sure there isn't any old grease blocking the grease and drain lines.


Clogging isn’t so much a problem here. It’s when the line -plastic or copper- rubs on the housing were it cuts behind the squirrel cage. That’s were it dumps it’s pile and you don’t know unless you remove the side of the AHU. The other new issue I’ve noticed is one of our maintance guys not installing the remote line back on. That’s just as much a PITA.


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## Westward (Mar 3, 2018)

My maintenance history says that failed bearings are the most frequent cause of motor service. Visual inspection typically picks up the clues. Expulsion of grease, contaminants, high overhung loads. We deploy IR thermal readings, Vibration analisys, annual greasing. The next major cause is thermal injury, largely caused by repeated starts. We increase our inspection frequency on any circuit that experiences a breaker or overload trip, ensuring that operations are instructed to notify maintenance on any trip, prior to restarting. I’ve seen many cases were well intentioned production crews reset an overload, only to have that stench fill the area on their 5 try.
We do record current draws on a weekly basis.


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## MDShunk (Jan 7, 2007)

If these are RTU's that would involve a crane to take them down to have a motor shop replace the bearings, it wouldn't be unreasonable (considering the cost of rigging) to run to failure and not fuss with measuring winding resistance and bearing monitoring. Just change belts and grease at the proper interval with the specified grease.


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## Lone Crapshooter (Nov 8, 2008)

Unless it is a large motor and the bearings can be lubricated it is run to failure. And put a new one in. The chance of a process upset it is just not worth it to shut a process down to check a $ 500.00 motor.

LC


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## joebanana (Dec 21, 2010)

Mr.Awesome said:


> Sweet we are on the same page. Thanks!
> 
> Only other question I haven't had answered yet...
> Largely due to the outdoor air pumping into the penthouse, everything gets grubby over time. Is it worth it to blow out the motors or is there too much risk of driving debris into the windings?


You should be using sealed motors for that application.


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## Mr.Awesome (Nov 27, 2015)

Shunk and Crapshooter,
The motors in question are strictly being used to move air. Top floor of an office tower in the penthouse. Not a major pain to take one out and down a flight of stairs to an elevator. Couple grand each so not ridiculously expensive. We do have some little dudes kicking around (small exhaust motors etc.) but I agree with you that they aren't worth the time to monitor heavily. Run until they die.
Part of my desire to start PM is simply learning for myself. Its completely on me to figure out things I have never done before and I'd like to get more motor experience under my belt. If learning this prolongs the life of these motors a bit longer, great! We aren't a plant so I have the luxury of shutting the units down on a warmer/cooler day (dependent on season) to play around with if I'd like.

I finally found some time to start figuring this out. I will gladly take all advice you guys give here, but I consulted a reputable motor shop in my city and they gave me agreasing interval table they recommend to clients. They also recommended Polyrex EM grease for compatibility with whatever might be existing in the bearings currently. I'm just going off that for now.

Their table goes off of frame numbers. First motor I've looked into is a 286T, which they state should be re-greased every 9500 hours and 0.61 ounces of grease added.
Regreasing dates are self explanatory, second portion was figuring out how many pumps 0.61 ounces is. I picked up a kitchen scale, zeroed it, and found 18 pumps out of the particular gun we have got me to 0.6 ounces. 
**(Does this sound like a ballpark number of pumps to you guys?)**

Now procedure. Poking around online, I'm gathering I pop the plug out of the bottom of the end cap, give my 18 pumps, run the motor for a half hour or so, then replace the end cap plug. I should also see some old excess grease run out.
**(Sound right to you?)**

If I wanted to purge the existing grease, I've found multiple resources that claim you simply remove the plug, stick a brush or something in to make sure there is no hardened grease obstructing the hole, and pump until the old is out and new starts squeezing out. Do you agree with this?

And not as much of a concern, but I didn't ask about the shaft bearings for the squirrel cages. Should I just use the same amount and intervals as the motors that drive them?


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## John Valdes (May 17, 2007)

When I worked in the motor shop we never gave this type of in house advice.
We always referred to the manufacturers recommendations. Everyone has an opinion as we have heard many times over.

I would not over think this. There is little you can do to prevent motor failure with the exception of over current and keeping the open frames cleaned out.
Belt alignment (mechanical) is also very important and will destroy a bearing long before a under greased bearing will. The right type of bearing for the application is also important. Example: Roller bearing vs Ball bearing.
Vibration is another area of concern. 
If I were you, I would inspect each contactor and OL to make sure they are sized properly.
Motors are dumb and will spin until they cannot spin anymore.
As someone said earlier. Mechanical problems are the the root cause of most motor failure.
Relax.


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## micromind (Aug 11, 2007)

I would look at the manipulate to see what type of grease the motor has and use that type only. If you mix greases, it'll end in disaster.....

Removing the drain plug, pumping in the proper type and amount of grease, running for 1/2 hour then replacing the plug is an accepted standard. Sometimes you'll have grease drain out, sometimes not. 

I would never completely fill a bearing with grease of any type. It'll heat up to the point of melting the grease and flinging it all over the inside of the motor. Eventually, it'll work its way into the end turns of the windings and attack the insulation. The motor will burn up shortly thereafter.


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## frenchelectrican (Mar 15, 2007)

Most common failure I get on electric motor typically bearing.

Most case useally caused by overgreased or wrong type.

but from time to time I get the bearing actually come apart so I take a look at the bad bearing to see what the clue is ., normal wear and tear or been under or greased or high sideload or trust load.

direct connected fans are famous for high trust load especally over 5 HP class and larger so I useally try to order one with oversized drive bearing to countertract the trust load.

Side load typically cause by overtighten belts some peoples do really make the belt super tight and can put alot of stress on bearing. ( the same for misalingment pullys )


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## paulengr (Oct 8, 2017)

The greasing advice is mostly correct. However we find a lot of motors won't actually purge grease properly regardless. So don't panic if it doesn't purge...may just be a design defect.

Second I cannot stress good design and installation enough. Good foundation, proper torque, alignment and balancing by the book. Good air flow, etc.

Third, visual inspection, cleaning, etc. Is very important. Vibration and thermal scans are good early warning tools. Checking for current and voltage balance keeps your power system and drive in check. Checking insulation resistance (graphically), coil resistance with a millliohm meter, and some kind of inductance test are done on more expensive motors and round out the predictive tests if the cost of repair is high enough to warrant it. We do this all the time in the Carolinas and Virginia because at around $100k for the test equipment, never mind training, it's beyond the reach of all but the biggest plants to do their own advanced testing.

Sent from my SM-T350 using Tapatalk


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## Mr.Awesome (Nov 27, 2015)

John,
I do not figure I'm overthinking. This is literally just something I was never trained to do and I'd like to know how to do it right. I did play around with the VFDs and found the motor information was never changed as the motors got changed out over the past few years. Also, "Motors are dumb and will spin until they cannot spin anymore.", I laughed at this probably harder than I should have.

micro, french, and paul,
Thank you for confirming what I had asked about. I KNOW theres currently mixed grease in there. The general maintenance guys over the years have just been throwing in whatever was on sale at the cheap hardware store. As stated before, I'm taking the shop's advice on the Polyrex as they stated it is compatible with most other greases and suited for the situation I have. There have also been multiple bearing failures over the past few years and I'd venture a guess its because of the random grease dumping.
I got my hands on a belt tensioner as well. I know the previous general maintenace guy would try to get the belts fiddle tight, then drop the motor a little when the belt stretched and started wobbling a bit.
Might be small potatoes for your industrial guys, but these are new skills under my belt.


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## John Valdes (May 17, 2007)

If you have belt driven loads, check the bearing type.
In many cases a roller bearing is the best bet for the application. Not all belt applications though.
Roller bearings are preferred when you have a heavy lateral load.
I have seen this so many times in the shop.
You do not have ex-ray vision so, you will need to wait for a failure or if the motor has been serviced, the motor shop should have the record. They should have a record of all your repair work. All equipment worked on is marked with a job number for easy recognition.

Example. OEM sells blower unit with correct motor. Motors goes out later and no one checks what type of bearing was used in the original motor. New motor fits fine but has wrong bearing for the job.
So you end up with a ball bearing where there was a roller bearing. 
Few if any motor manufactures build stock motors with roller bearings. Its a special order or you must have the shop change it for you. This motor likely needs machine work to accomplish this.

Note: Most all direct couple motors do not need or use roller bearings. Belt driven loads do "sometimes". In some cases a "Maxi Ball Bearing*" can be substituted for roller "sometimes".

Relax.

*Trade name for ball bearing designed to be used in lieu of roller bearing. No machine work required, but not as good as roller.


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## Moonshot180 (Apr 1, 2012)

for bearings, we use SKF ALOT...

http://www.skf.com/us/index.html


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## paulengr (Oct 8, 2017)

Polyrex EM. The EM is important. Regular Polyrex has an EP additive which is good for general use but not motors. Bigger motors occasionally use lithium grease but for anything under about 100 HP you won’t ever see anything else. Be forewarned that if you mix greases some greases will actually attack the other one and cause the suspension to collapse leaving you with worthless dirty oil and no lubrication. Most “cheap” greases are just lithium greases because it’s inexpensive.

Keep in mind some of this stuff is general and some is specific to the application.

If you want to see expensive price put a tube of Molykote 3451 circuit breaker grease.

Invest in torque wrench and screwdriver too. IEAE did a study and found even most professional electricians don’t tighten bolts and screws enough. Or get an impact gun and use torque sticks. Faster and easier on your arms.


Sent from my iPhone using Tapatalk


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## Mr.Awesome (Nov 27, 2015)

Torque wrench is on the shopping list. I've swayed them to start replacing some of the 60+ year old equipment. May as well take care of it.


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