ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Conduit over Vinyl Siding
by Jim M - 06/16/21 08:30 PM
Updated Forum Software
by Admin - 06/15/21 10:23 AM
Broken Outlet & Dangling Light
by LoneWolf - 06/14/21 08:21 PM
How's all our Non-US folks doing?
by C-H - 06/14/21 05:42 PM
Where is Everyone?
by Bill Addiss - 06/14/21 12:37 PM
New in the Gallery:
2020 - 2021 Winter Project
2020 - 2021 Winter Project
by Bill Addiss, April 29
Garden 2021
Garden 2021
by Bill Addiss, April 26
Who's Online Now
0 members (), 11 guests, and 17 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#89513 09/22/04 02:54 PM
Joined: Dec 2002
Posts: 308
E
Edward Offline OP
Member
I went out to an steel whole seller plant. In the yard they have a huge crane that moves and loads steel. which is being fed by #2AWG from a 225Amp three phase breaker. Next to that panel they have another panel with a 20Amp/3 phase breaker that powers 277Volt lighting. When i opened both panels i did not see a grounded(neutral) conductor. The way they are getting the 277 from 480 is they are using the grounding in this case the frame of the panel.

This is clearly in violation. Right?

Or am i missing something here?

Thanks
Edward


Thanks
Edward
2017 / 2014 NEC & Related Books and Study Guides
#89514 09/22/04 03:39 PM
Joined: Jan 2003
Posts: 4,391
I
Moderator
What makes you believe the lighting is 277, it might be 480 volt and what you think is neutral is really the EGC.

But if it is 277 lighting run from a 480 panel with no neutral, yes it is a serious violation.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#89515 09/22/04 03:59 PM
Joined: Dec 2002
Posts: 308
E
Edward Offline OP
Member
The reason i know it is the neutral because there are three colored conductors and one grounded(neutral) going to the lighting fixtures. Besides there are photo cells that control the lighting fixtures which are rated for 277 and have a neutral conductor.

Thanks
Edward


Thanks
Edward
#89516 09/22/04 04:59 PM
Joined: Jan 2003
Posts: 4,391
I
Moderator
Not having seen the installation it sounds like a violation.

The reason I asked about the voltage is that it is common to run site lighting from a 480 volt 3 pole breaker. Some fixtures on phases A - B some on B - C and others on C - A.

There would be no reason to use a 3 pole breaker if these lights are 277 volt, three single pole breakers would normally have been used for this.

I would say it is bad to assume that just because you see a white wire that it is a neutral. Although using a white wire for the EGC would also be a violation.

The photo eyes definitely sound like a violation as I they do use a neutral as you pointed out.

You could Mickey Mouse three (or even 2) 277 volt single pole photo eyes to control a 3 phase 480 volt feed. But that would be a violation also.

Bob


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#89517 09/22/04 10:03 PM
Joined: Mar 2004
Posts: 947
T
twh Offline
Member
I saw this type of Mickey Mouse set up, too. I assumed that it was a result of not being able to get a 480 volt photo cell.


Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
lil suzi
lil suzi
Midwest
Posts: 57
Joined: August 2003
Top Posters(30 Days)
Admin 14
Trumpy 10
Popular Topics(Views)
280,410 Are you busy
213,482 Re: Forum
200,390 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5