×
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

Asym L-L, Sym L-L, L-G Fault Data (?)

Asym L-L, Sym L-L, L-G Fault Data (?)

Asym L-L, Sym L-L, L-G Fault Data (?)

(OP)
Greetings,
I have received available fault current data from the utility in the form of L-L instead of Three phase. I have not seen this before from my local utility. I am wondering if this is a mis-speak because I was given this data third hand.
I have not been successful reaching the utilty planner to clarify so I was wondering if there are any thoughts out there....
Given the L-L sym and asym and the L-G fault current, is it possible to calculate the three phase?  

RE: Asym L-L, Sym L-L, L-G Fault Data (?)

Maybe it's a V-phase line?  

If not, I'd ask for clarification.   

RE: Asym L-L, Sym L-L, L-G Fault Data (?)

If you assume Z1=Z2, then the two values should be enough to calculate the unknown Z1 and Z0 values.  From Z1, you can calculate the 3Ø fault.  Actually, if Z1=Z2, then I = 2·IL-L/sqrt(3).

You still need clarification.  Most likely, you have a 3Ø fault value, not a L-L value.  If it is L-L, is it L-L or double Line-to-Ground?  Without knowing what you have, it's no use calculating anything.

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