×
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

settings distance protection and OC protection

settings distance protection and OC protection

settings distance protection and OC protection

(OP)
We have two realay protection in HV lines Distance protection and overcurrent protection. The time settings of backup overcurrent protection for earth fualt is 1 sec. During single phase short circuit the trip issue by main distance protection and ARC start in progres. The dead time ARC is 1sec. Some time because one phase is triped during dead time is appear high level values of IE>. This value pickup overcurrent protection and issue the trip also for 1 sec. How we can solve the problem to change the time of OC protection or to increase settings IE>. Please I want your comment and experience.

RE: settings distance protection and OC protection

If you are single pole tripping you have to disable all ground/earth protection that might be affected by the pole open condition  during the time that you have an open pole.  1 sec backup protection time sounds rather long; with two sets of distance relays why are you doing overcurrent backup any way?

RE: settings distance protection and OC protection

Yep. David is right.
In case of single phase AR you must block directional E/F protection or chanage time to longer.
David, in our systems, directional ground fault relay with time 1-1.2sec too, but we don't use simple overcurrent relay for back up distance.
Best Regards.
Slava

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