×
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

Why only equilizer winding completely burnt in 60kW TEFC motor, after full load run for 8 hours ?

Why only equilizer winding completely burnt in 60kW TEFC motor, after full load run for 8 hours ?

Why only equilizer winding completely burnt in 60kW TEFC motor, after full load run for 8 hours ?

(OP)
Hi,

There is problem reported in our 60kW DC Motor.
We had run this DC motor on full load & after running of 8 hours , the motor was failed.

And during failure analysis it observed that all winding like field winding, IP winding, series winding & Armature winding found healthy, even commutator was also healthy.

After opening of layers of armature winding it was observed that equalizer winding was completely burnt.

Kindly suggest the possible causes of failure...


Regards,
Mahesh

RE: Why only equilizer winding completely burnt in 60kW TEFC motor, after full load run for 8 hours ?

Conductor failure in general can be initiated due to excess current or due to insulation breakdown.

Your description "completely burnt" seems to point in the direction of excess current. It was the entire length of the equalizer? All equalizers?

What is ratio of equalizer conductor area to armature coil conductor area? Should be at least 1/3, maybe more depending on design, per EASA.

The purpose of the equalizer is to prevent differential voltages of points that are supposed to be equal voltage (allows small current circulating in small loop to avoid larger current circulating in larger loop). The unbalance can arise from uneven airgap, problems with magnetic circuit, perhaps more. It seems that excess unbalance could overload the equalizers (the unbalance circulating current also flows in armature coils, but those have larger conductors).


=====================================
(2B)+(2B)' ?

RE: Why only equilizer winding completely burnt in 60kW TEFC motor, after full load run for 8 hours ?

(OP)
Thanks,

I presumed the same.....


Regards,

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