×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Core loop test

Core loop test

Core loop test

(OP)
How would you compare a stator core loop test to El Cid test? What are the advantages and disadvantages of both?

Sarg

RE: Core loop test

El Cid is low power test.  Supposedly it has less ability to find problems deep within the core since it does not excite the whole core.  

Loop test can be somewhat difficult to setup and run.  Then again, it may be there is equipment available to run the loop test without special purchase.  El Cid is most definitely a special-purpose machine with one use only.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: Core loop test

Below is excerpted from an article on Adwell's website (manufacturer of el-cid device).  Obviously possible bias of the author must be considered.

"The alternatives to the Electromagnetic test are usually core loss testing, or high power Ring Flux testing using thermal checks or IR imaging to detect defects. The former will fail to pick up small local faults which do not contribute significantly to the loss, but which could still lead to serious local over-heating. In addition no information about fault location is provided.
The latter test has the disadvantage that high voltage and current levels can be needed, time is required to allow local hot-spots to become established, and there is a risk of causing further damage to a defective motor core since the normal motor cooling is not functioning. In addition faults buried in the core may not be evident, and if they are near a conductor slot will affect insulation life.
The Electromagnetic test avoids all these disadvantages and
also has the ability to detect faults in slots with the windings still in place. Further, as the test does not cause any heating and can be repeated on a repair at any time, the effectiveness of repair work can be immediately assessed as it progresses. It may also be applied as a QA check on machines in production, remembering that a 10% over-temperature on winding insulation can reduce its life by 50%."

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: Core loop test

Before I get myself in trouble I should say loop test is normally performed in repair shop with core loss tester (like Lexeco) which is a special purpose piece of equipment like el cid.  It may also be possible with other power supplies with careful consideration of impedance, but in that case the value would be limited to measuring temperature rise and hot spots.

If it is done with a core tester you also can measure watts per pound. That is widely used as a measure of possible core degradation during stripping of stator winding prior to rewind of motors.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources