Motor Squealing After Reversing Rotation

[lbell101]

Bought a new head for my compressor. It required reversing the direction of rotation. So I swapped two of the line leads. Rotation reversed but now I'm getting a squeal. I've only tested it with no load but it didn't squeal in the other direction with no load. The noise only starts after it gets to speed and cuts out during slowdown but before it';s stopped. Any ideas? Could I have wired it wrong?
Thanks!

Larry

 

[aolalde]

Please post the nameplate data and the wiring diagram.

 

[electricpete]

I assume you changed two things at one time:
New compressor head.
Reverse motor direciton.
Afterwards you have a squeal.

Is it possible the squeal is not caused by change in direction but by change in compressor. Can you tell if noise is coming from motor or compressor?

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[pennpoint]

Belt Squeal perhaps...

pennpoint

 

[SteveKW]

Shaft slinger rubbing?

 

[lbell101]

Thanks guys!

It was a squeal under no load (no belt on). But it appears to have disappeared now. Possibly dirt or just an akward shift inside caused the noise? I put the belt and let it pump up and all seems well. Nothing running hot or noisy now. I would have felt better about my rewiring if the tag was legable.
Thanks for the help!

Larry

 

[SteveKW]

Hmm...
Because of the twist in the rotor bars, would reversing the rotation change how the stator "pulls" the rotor either towards the shaft end or opposite shaft end?

 

[jraef]

SteveKW,
Maybe if it had been running one direction for a long time with a lot of start cycles. Hey, wait, sounds like a compressor!

lbell101,
If it was a 3 phase motor, and it ran in reverse after you hooked it up, you couldn't have wired anything wrong. It's not that complex.

"Venditori de oleum-vipera non vigere excordis populi"