×
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

Current Limiting Reactor
3

Current Limiting Reactor

Current Limiting Reactor

(OP)
I have two questions:
1. Where can I find the X/R ratio of a 3ph, 12.6 kV, 5%, 600A reactor?
2. I calculated the MVA rating of this reactor as follows:
1.73x12.6x600/1000=13.1 MVA. Is this correct?

Thanks,
kingi

RE: Current Limiting Reactor

1.  The manufacturer
2.  Yes

Mike

RE: Current Limiting Reactor

(OP)
Thank you for your reply. I took the information from a drawing where the manufacturer was not mentioned. I wonder what would be the approximate X/R ratio for a similar series reactor?

Thanks,
kingi

RE: Current Limiting Reactor

Kingi-

It's impossible to accurately speculate. The Q-factor (X/R) varies substantially with design and even within designs of the same manufacturer.

RE: Current Limiting Reactor

Conrad St. Pierre's book, "A Practical Guide to Short-Circuit Calculations", has some curves in the Appendix for typical air core reactor X/R, depending on the conductor material.

For a 13.1 MVA reactor, the range for X/R is on the order of 40 to 70.  

RE: Current Limiting Reactor

(OP)
Thank you all. I didn't think the X/R ratio was that high.

kingi

RE: Current Limiting Reactor

If you know what the conductor material is, I can give you an equation for an approximate calculation of X/R.  

It will still be quite a few watts of heat loss when you run the numbers out, since you're dealing with the square of the current.  

RE: Current Limiting Reactor

DPC-

I seriously question that table you reference based on conductor material as being accurate (of course 40-70 is a huge range). There are many different types of winding and conductor profile configurations for air-core reactors...and i say that as someone who works for a reactor configuration.

Just my $0.02 worth.

RE: Current Limiting Reactor

scottf,

It's the same chart and equations that GE has referenced for years, I think.  



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