×
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

Inrush on large autotransformers

Inrush on large autotransformers

Inrush on large autotransformers

(OP)
Hi

Anyone tell me what are typical maximum inrush values one can expect on large autotransformers (>200MVA, >=220kV)? I need to set the diff hi-set element on a 375MVA, 275kV unit.

Thanks.

RE: Inrush on large autotransformers

Anything like 5-8times full load current.But better to get the figure from the manufacturer.

RE: Inrush on large autotransformers

(OP)
prc

This seems to be the general rule of thumb for trfr inrush. But I have also seen that for small units (< 5MVA ) it can be up to 10p.u. and someone said for large autos you can look at 2.5p.u..

Are there perhas more specific rule of thumbs depending on trfr size?

Thanks.

RE: Inrush on large autotransformers

No thumb rules.Inrush varies due to various factors.Transformer size is a parameter. In a voltage  transformer it can be 25 times rated current. In a distribution transformer 10-15 times FLC.Power Transformers 8-12 times and very large units 3-5 times.For the size mentioned by you and for auto transformers the range mentioned by me is normal.

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