Vibration standard for electromotor
Vibration standard for electromotor
(OP)
Dear all,
Does anyone know about vibration international standard of electromotor?
Thank you
Does anyone know about vibration international standard of electromotor?
Thank you





RE: Vibration standard for electromotor
Muthu
www.edison.co.in
RE: Vibration standard for electromotor
NEMA MG-1 identifies vibration requirements for new motors: < 2 mils, 0.12 ips, 0.8 ips when tested on rigid mount. < 2.5 mils, 0.14ips, 1g when tested on resilient mount. I specify rigid mount whenever possible because resilient mount can hide soft-foot conditions and you don't the first time you find out about that to be when the motor is installed into the plant (been there, done that, not fun).
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
That soft foot condition (2xline frequency) can't be corrected by shimming. You meant it for resilient or rigid mounts ? In any case, why it cannot be corrected ?
Muthu
www.edison.co.in
RE: Vibration standard for electromotor
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
Sorry to get way off track. The main point was that whenever I mention the NEMA specs, I always tell people to test rigid mount. NEMA is imo silly to allow anything different for motors that are going to be installed rigid-mounted.
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
Just last week, I had a client with 2 pole, 3600 RPM (VFD) motor with high vibration issues. We brought down the horizontal and vertical vibration from over 18 mm/sec rms at both axes to 1.5 mm/sec. All vibrations were 1X. Balancing and rectification bearing housing concentricity fixed the problem.
Muthu
www.edison.co.in
RE: Vibration standard for electromotor
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(2B)+(2B)' ?
RE: Vibration standard for electromotor
RE: Vibration standard for electromotor
Thank you
RE: Vibration standard for electromotor
It is harder to implement up front, but weeds out real problems better than an overall that of necessity is chubby and blind.
0.1 IPS pk of "unbalance" is less important than 0.1 IPS of bearing screech and rumble, or the 2X LF that EPete and others mentioned.