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Does this VIDEO depict a bad 3 phase motor?

I sold a supposedly rebuilt 3 phase 10 hp motor to a customer.

The customer contacted me and is claiming that the motor is defective, citing vibration and noise.

I asked him to make a video.

As a proof of this, he produced the following video:

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As I watched it, and looking at the water in cup, I could not but feel that it is a totally normal motor. However, as I would like to be sure of whether I am right, or wrong, I wanted to ask your opinion.

Does the above motor sound bad and does it vibrate excessively?

thanks

Reply to
Ignoramus26205
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HUH? What is WRONG with the guy? The water is BARELY moving at ALL! I'm not sure the sound in a YouTube video is good enough to tell much, but it didn't sound wrong. If he wants a super-balanced motor, he's going to have to go to a Fanuc spindle motor or something.

One doesn't expect a 10 Hp motor to "purr like a kitten". Also, if he's using a rotary phase converter or something like that, even though his L-L voltage is well balanced, the motor may have slightly more vibration than with a real 3-phase mains supply.

Jon

Reply to
Jon Elson

He has it mounted on a hard / semi-rigidity / wood pallet. He should have it on shocks like an isolated rubber sheet without bolts through making the thing hard again.

Rubber washers top/bottom with metal washers to transfer bolt head and nut to keep within bounds but not hold tight. Let the motor float in the bounds.

If the need is so tight, then he should go multi-phase and super balanced with super bearings. The winding's have to be matched.

Mart> I sold a supposedly rebuilt 3 phase 10 hp motor to a customer.

Reply to
Martin Eastburn

So you're wondering if it's an Al Special rebuilt (blow off and repaint sans masking) or an actual rebuild?

A 10hp motor with three or four tenths of vibration? Get out. That big guy is purring.

There's a little something in the sound that bothers me on a minor level, but I'd want a stethoscope to verify that it's from one of the motor bearings and nothing else in the room. Just a harshness. I wonder if a screwdriver held against the bearing housing and up against the phone would pick anything up.

Reply to
Larry Jaques

Iggy, I'm no motor expert, but that one seems a little noisier than any of the 3 phase motors I am running. Mine are all running on variable frequency drives though so the power delivery is very consistent. Some of the equipment some of my motors is connected to makes some noise, but when the drive belts are off they are pretty quiet.

Reply to
Bob La Londe

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