It is currently Mon Aug 03, 2020 10:13 pm



Post new topic Reply to topic
Author Message
ekstra   ara
 Post subject: Lock-out relays
PostPosted: Fri Dec 04, 2009 2:24 pm 

Joined: Thu Apr 02, 2009 5:59 am
Posts: 6
Hi everyone,

I am doing an arc flash study for a generating station that protects the main generator buses through lockout relays (i.e. 50/51/87 etc. element actuates the 86 element which in turn initiates the circuit breaker trip coil). It turns out there is a wide variance of activation times on these lockout relays (from reading on-line specs) and it is not particularly easy to get this data from the client. How does everyone incorporate the 86 element time into their model? I have heard times ranging from 130ms all the way down to 8ms... makes a pretty big difference in HRC.

Thanks in advance for the input.

Tim Ricard


Top
 Profile Send private message  
Reply with quote  
 Post subject:
PostPosted: Fri Dec 18, 2009 11:21 am 
Arc Level

Joined: Tue Jan 13, 2009 5:00 pm
Posts: 532
Electroswitch says .5 cycle.


Top
 Profile Send private message  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 7 hours


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
© 2019 Arcflash Forum / Brainfiller, Inc. | P.O. Box 12024 | Scottsdale, AZ 85267 USA | 800-874-8883