Previous in Forum: Discrimination Regarding   Next in Forum: ABB IMBD 145 A4 Test Voltage
Close

Comments Format:






Change Mode
Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







Add Vote
2 comments
Rate Comments: Nested
nesubra
Guru

Join Date: Nov 2006
Posts: 729
Good Answers: 2

Bearing Insulation

09/30/2011 9:47 AM

The standard practice on large electric motors is to insulate bearing at one end which is normally NDE.Is it necessary to insulate bearings at bot ends?I have read long back that insulating both ends can result in a large static build up as no discharge path exist.( So you have to provide a shaft grounding brush)is it really necessary to insulate both ends?

__________________
 To avoid crticism do nothing,say nothing,be nothing
Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Anonymous Poster #1
#1

Re: Bearing insulation

09/30/2011 11:10 AM

and an ancient Tibeten philosophy said do nothing be nothing.Did you see 'The Losers' movie?
Register to Reply Off Topic (Score 6)
TonyS
Guru
United Kingdom - Member - New Member

Join Date: Aug 2010
Location: Resting under the Major Oak
Posts: 4347
Good Answers: 181
#2

Re: Bearing insulation

09/30/2011 11:34 PM

Normal practice is to insulate both bearings but then add an earthing strap to one bearing only. This enables insulation testing by removing the strap. Alternatively as you say a grounding brush can be used to replace the earth strap but both the bearings still have to be insulated.

At the end of the day your trying to prevent circulating currents in the rotor shaft through the bearings.

__________________
 The reports of my death are greatly exaggerated.
Register to Reply
Register to Reply
Have a Different Question?
2 comments

Previous in Forum: Discrimination Regarding   Next in Forum: ABB IMBD 145 A4 Test Voltage

Advertisement

Got Something to Say?
Ask a Question
Start a Discussion

Search this Forum
Electrical Engineering:
Go

CR4 Sections
Aerospace
BioMech & BioMed
Chemical & Material Science
Civil Engineering
Communications & Electronics
Education and Engineering Careers
Electrical Engineering
General Discussion
Instrumentation
Manufacturing
Mechanical Engineering
New Technologies & Research
Software & Programming
Sustainable Engineering
Transportation

Site Directories
Forum Directory
Blog Directory
User Group Directory
RSS Feeds

CR4 Rules of Conduct
CR4 FAQ
Site Glossary

Who's Online (75 right now)
Show Members
Advertisement