×
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

IEC Power Transformer Ratings

IEC Power Transformer Ratings

IEC Power Transformer Ratings

(OP)
HI all, I have a 7/8.75MVA power transformer rating. Is this an IEC MVA rating?

My calculated maximum demand load for a 34.5-4.16kV stepdown transformer is 10.294MVA. May I know what OA/FA IEC transformer rating would fit my purpose?

I have no access to IEC rated transformers. Thanks.

RE: IEC Power Transformer Ratings

IEC 60076-1 doesn't mandate power ratings for transformers, but for ratings under 10MVA, they have preferred values based on the R10 series of ISO 3 (with reference to IEC 60076-1 Clause 4.3).

The ISO 3 preferred numbers are in turn based on Renard numbers (e.g. see http://www.sizes.com/numbers/preferred_numbers.htm). So for your first question, 7000kVA is not a preferred number (however 6300 and 8000kVA are).

For your second question, IEC 60076-1 doesn't say anything about preferred ratings over 10MVA, so you can choose whatever rating you like. Realistically, you should probably check with your trafo manufacturer.

RE: IEC Power Transformer Ratings

(OP)
Thank you for the ISO 3 information

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