It is currently Tue Dec 07, 2021 6:12 pm



Post new topic Reply to topic
Author Message
ekstra   ara
 Post subject: EasyPower Integrated Method
PostPosted: Wed Dec 03, 2008 6:54 am 
Plasma Level
User avatar

Joined: Wed May 07, 2008 5:00 pm
Posts: 862
Location: Rutland, VT
I was curious to see how many people that using EasyPower are using the Integrated method for finding the AFH when there are multiple sources. Per EasyPower, "this method takes into account the decreasing currents from motors and generators and also from multiple sources being switched out through protective devices tripping. The integrated method is the closest to a realistic scenario."

_________________
Barry Donovan, P.E.
www.workplacesafetysolutions.com


Top
 Profile Send private message  
Reply with quote  
 Post subject:
PostPosted: Wed Dec 03, 2008 7:35 am 
Sparks Level
User avatar

Joined: Mon Nov 10, 2008 1:08 pm
Posts: 60
Location: Cincinnat, OH
I have used it in the past and it does make a huge difference and model what is more realistic in the field. One of the nice things that it does as well, is it allows motor contribution to decay, depending on the facility you can have some large motor currents contributing. Also it keeps calculating at set intervals so when sources drop out that contribution is no longer being factored in. Typically the calculations use maximum magnitude fault for the longest duration of the last source clearing.


Top
 Profile Send private message  
Reply with quote  
 Post subject:
PostPosted: Thu Dec 04, 2008 4:26 am 
Plasma Level
User avatar

Joined: Mon Sep 17, 2007 5:00 pm
Posts: 1630
Location: Scottsdale, Arizona
This is one of those areas where motor contribution modeling was not well defined in IEEE 1584. Until what I would consider this more realistic model was developed, motor contribution was a bit ackward. If you include it, often it would appear as sustained which is not correct and could effect the incdent energy. I would often try modeling incremental percentages of motor contribution just to see what happened.

I talked directly with EasyPower about their model several months ago. They explained the decay method they are using which I thought was quite good. They take the more realistic approach of the dynamic nature of the decay so the initial event (t=0) has all of the motor contribution then it decays over several cycles.

_________________
Jim Phillips, P.E.
Brainfiller.com


Top
 Profile Send private message  
Reply with quote  
 Post subject:
PostPosted: Fri Aug 28, 2009 5:15 am 
Sparks Level
User avatar

Joined: Sun Aug 16, 2009 8:42 am
Posts: 184
Location: Lawrenceburg KY
Yes. Great software at least for me.


Top
 Profile Send private message  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 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