It is currently Thu Dec 03, 2020 6:38 pm



Post new topic Reply to topic
Author Message
ekstra   ara
 Post subject: Missing Panel Screws
PostPosted: Fri Mar 27, 2020 6:59 am 

Joined: Mon Mar 09, 2020 9:27 am
Posts: 5
Is there any real difference in arc flash events when a panelboard is missing screws or using sheet metals screws instead of machine screws? For example if a snake slithers in and wraps around the bus bars. Would a person standing in front the the panel be worse off either way? I've read some posts here and it seems like the arc blast is not as significant as in safety videos.

Any references to a scholarly article that makes mention would be nice too. Thanks in advance.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Missing Panel Screws
PostPosted: Sun Apr 05, 2020 1:45 pm 
Plasma Level
User avatar

Joined: Mon Sep 17, 2007 5:00 pm
Posts: 1528
Location: Scottsdale, Arizona
From the arc flash study perspective, it wouldn't matter since it is assumed the door/cover is open. From a practical view, the exact answer is "it depends" I don't know of any way to evaluate how it would respond. In a forensic analysis (especially if someone was injured) that could become a significant issue.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Missing Panel Screws
PostPosted: Mon Apr 06, 2020 9:37 am 
Sparks Level

Joined: Tue Jan 19, 2010 2:35 pm
Posts: 144
Your question is one I've been asked.
When talking about arc flash, I generally default to what a manufacturer's defense would be if their equipment was involved in an arc flash. One of the first questions they'd ask is, "was the equipment maintained to our recommendations?" Or, "did you use another type of fastener, like a sheet metal screw?" Or "were all of our fasteners installed and was the hardware free of rust?" Or "were all the fasteners installed and tight?" If you answered "no" to any of the questions, they are likely not liable. The argument would be "how can a manufacturer be held liable if the user fails to follow our published instructions? That's a very fair question. When I talk to facility staff about leaving a screw or two out of a dead front, I'll them the same question.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Missing Panel Screws
PostPosted: Mon Apr 20, 2020 4:48 pm 
Sparks Level
User avatar

Joined: Sun Jan 04, 2009 5:00 pm
Posts: 285
Location: Louisville, KY
Here is the latest paper on blast pressure. I have a newer one but not yet in the Transactions. In final editing for publication.

https://ieeexplore.ieee.org/document/7565738

Let me know if I can help.

Hugh Hoagland


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