×
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

Separation of copper and iron weights in transformers

Separation of copper and iron weights in transformers

Separation of copper and iron weights in transformers

(OP)
The transformer nameplates normally give the weight of core + winding together. Anyone has any idea in what proportion is this weight distributed ? Is assuming 40% is copper reasonable ?  

RE: Separation of copper and iron weights in transformers

(OP)
I was talking about oil-filled transformers.

RE: Separation of copper and iron weights in transformers

This is an interesting question which was raised to me by two sources last year-one a transformer repairing company and other by a local power utility who was scrapping transformers.Then I understood the need for  a separate name plate on transformers- Salvage or recycling plate or something like that.This plate should carry the net weight of copper,silicon steel,mild steel and oil used in the transformer.I am pushing industry on those lines.To get this information of a 40 year old transformer is extremely difficult-manufactuers will not be ready to search for this info.

Coming to edisons query-net weight of copper plus silicon steel will be total weight of active part divided by k. K will be 1.25 to 1.15.Trfs prior to 1975 k=1.25,1975-1995-1.2,after 1995,1.15.
Division of core by copper ratio will be 1.5-4 for two winding trfs and 1-2 for auto transformers.This depends on the loss capitalisation used at that time.If core loss to copper loss capitalisation rate is nearer to one,core by copper ratio will tend towards one.If it is high,core by copper will move away from one.

RE: Separation of copper and iron weights in transformers

(OP)
Thank you prc. I have got an enquiry for a trafo (circa 1968) rewinding and given today's copper's volatile prices, I was looking for ball park number. To be on the safe side, I will take it as 1:1.

I agree. It is time that trafo manufacturers quantify these separately on the nameplates.

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