| Author |
Message |
|
Jim Phillips (brainfiller)
|
Post subject: Largest Arc Flash Boundary  Posted: Sun Jul 23, 2017 12:54 pm |
|
| Plasma Level |
 |
Joined: Mon Sep 17, 2007 5:00 pm
Posts: 1737
Location: Scottsdale, Arizona
|
|
Last week’s question was about large incident energy calculation and this week’s question parallels that theme.
It is about large calculated arc flash boundaries. Of course, actions such as using a 2 second cut off, adding arc energy reduction methods etc. can reduce the boundary but without those actions:
What is the largest calculated Arc Flash Boundary that you have seen?
Less than 10 feet (3 meters)
Between 10 feet (3 meters) and 30 feet (9 meters)
Greater than 30 feet (9 meters) – How large was it?
|
|
| Top |
|
 |
|
Doug Powell
|
Post subject: Re: Largest Arc Flash Boundary Posted: Mon Jul 24, 2017 1:33 pm |
|
Joined: Wed Sep 12, 2012 9:13 am
Posts: 18
Location: Northern Colorado USA
|
|
Recently calculated a 19' boundary based on a 13.8kV/480V, 3PH, 800 kW transformer. Incident energy at the working standard distance for a panelboards was quite high and exceeded the 40 cal/cm2 limit. I did factor a 16' cable run and probably should increase that by quite a bit more. I am not certain how to calculate complex impedance for 3PH direct bury. Think you could do a blog post on that someday and include number of conductors for each phase?
~ Doug
|
|
| Top |
|
|
 
|
Page 1 of 1
|
[ 2 posts ] |
|
|
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
|
|
