Swapping from a 143T to a 143TC motor

[Pevehouse]

Small word of caution would be that your iron lines back up; as in the rotor core (the laminations of the rotor) should as centered as possible with the laminations of the stator. Most motors either the endbells or the stator core is offset from the frame to allow room for the extra wire on the connection end. Changing the motor from f1 to f2 (orientation if the Cbox) or vice versa could cause the mechanical center to change from the magnetic center which will take up your endplay causing excess bearing wear due to axial load and higher operating currents as the motor is constantly trying to pull the rotor back to magnetic center. Granted this only become a noticeable problem is the to centers are way off, you'll know right away if the rotor darts one direction on startup or starts to oscillate from bouncing off the wave spring as the mag center tries to pull it back and one endbell gets warmer much faster than the other.

I understand exactly what you’re saying. Had to read it twice,lol. I measure the windings and they seemed pretty centered in the case. As far as the offset goes I’m not 100 percent sure if one side was offset but the motor appears to be designed to run either setup. F1 or F2. It’s the most versatile motor I have ever came across. I have a temp gun and an amp meter. What should I look for to verify everything is ok?

 

[Ulma Doctor]

Sound of the motor will tell you most of what you need to know.
If it sounds funny, something is wrong.
By all means perform an amp draw test and voltage testing if you are curious

 

[Alter Machine]

I understand exactly what you’re saying. Had to read it twice,lol. I measure the windings and they seemed pretty centered in the case. As far as the offset goes I’m not 100 percent sure if one side was offset but the motor appears to be designed to run either setup. F1 or F2. It’s the most versatile motor I have ever came across. I have a temp gun and an amp meter. What should I look for to verify everything is ok?

So generally the drive end bearing configuration (the end with the shaft extension) controls end play, something were to bind it would be there creating heat, the non drive end (fan end) has a wave spring or a deeper machined bore to allow for thermal expansion (this allows the shaft to grow in a direction that won’t affect the alignment of whatever it’s driving) and typically runs cooler. In a typical 3 phase configuration after the initial inrush current dissipates you can expect the motor to run at 10%-25% of its full load amps. If after say 5mins of running the current continues to climb as well as the heat in the drive endbell your mechanical center and magnetic center are fighting each other or something is misaligned. Theres also a telltale “scree” of bearings skidding axially against their raceways it sounds like a bird chirping listen for that as well.
Sorry if I’m creating confusion for you. This just a friendly heads up from a guy who works in the motor repair industry of the challenges that arise when we modify a design. I’m sure it will be fine as baldor usually is pretty good at building motors that are easily configurable to a given application but can’t hurt to check.

 

[Pevehouse]

So generally the drive end bearing configuration (the end with the shaft extension) controls end play, something were to bind it would be there creating heat, the non drive end (fan end) has a wave spring or a deeper machined bore to allow for thermal expansion (this allows the shaft to grow in a direction that won’t affect the alignment of whatever it’s driving) and typically runs cooler. In a typical 3 phase configuration after the initial inrush current dissipates you can expect the motor to run at 10%-25% of its full load amps. If after say 5mins of running the current continues to climb as well as the heat in the drive endbell your mechanical center and magnetic center are fighting each other or something is misaligned. Theres also a telltale “scree” of bearings skidding axially against their raceways it sounds like a bird chirping listen for that as well.
Sorry if I’m creating confusion for you. This just a friendly heads up from a guy who works in the motor repair industry of the challenges that arise when we modify a design. I’m sure it will be fine as baldor usually is pretty good at building motors that are easily configurable to a given application but can’t hurt to check.

No sir , no confusion. I could tell you knew what you were talking about. I really appreciate you giving me the heads up on it. I would have never known these things. This kind of stuff is very interesting to me and I could go on for days listening to all the technical details of how motors work,lol. Thank you

 

[Pevehouse]

Sound of the motor will tell you most of what you need to know.
If it sounds funny, something is wrong.
By all means perform an amp draw test and voltage testing if you are curious

Yes sir, I kind of figured I should be listening for any funny noises when I fire it up. I think it’s gonna be fine though. Theres no binding or any thing like that. Everything went together just fine as well. Now on another note, Alter Machine went into deep detail on it, I would have never guessed that the spring washer was for thermal expansion. I really appreciate both you guys helping me out

 

[Pevehouse]

Well, I got it mounted and wired but as you guys suggested, I have a low growl from the motor. I have not run it long but the end caps seem to be cool and my vfd has had no current or amperage faults. Not sure how these motor normally sound .

 

[Pevehouse]

Well, I got it mounted and wired but as you guys suggested, I have a low growl from the motor. I have not run it long but the end caps seem to be cool and my vfd has had no current or amperage faults. Not sure how these motor normally sound .

I guess I could post a video so you guys could hear it

 

[Pevehouse]

I guess I could post a video so you guys could hear it

 

[Ulma Doctor]

Sounds like the fan may be rubbing on the fan shroud, looks like a small dent in the shroud around the 1 o’clock position of the shroud

 

[Pevehouse]

Sounds like the fan may be rubbing on the fan shroud, looks like a small dent in the shroud around the 1 o’clock position of the shroud

I took the fan off. It’s still there. I can slightly loose the rear cover bolts and the noise almost goes away. I’m thinking alter machine was spot on with his warning. Looks like I’m gonna have to reverse everything back and regroup