ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

ECN Shout Chat
Top Posters(30 Days)
Admin 16
Recent Posts
ESA Arc flash course
by TheShockDoctors. 03/24/17 10:15 AM
fuse rejectors
by HotLine1. 03/24/17 07:53 AM
Another Forum Update
by Admin. 03/22/17 03:04 PM
Dining room plugs
by watersparkfalls. 03/21/17 10:31 PM
TRUE POWER
by jraef. 03/21/17 09:13 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
231,369 Are you busy
166,092 Re: Forum
160,560 Need opinion
Who's Online Now
0 registered members (), 59 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#43328 - 10/10/04 10:13 PM nuetral question  
rj  Offline
Member
Joined: Jan 2003
Posts: 21
Skidmore, Missouri, USA
This might be a dum question and it mighthave been asked before, but here goes. Why does the nuetral always seem to burn? Me and the guys I work with have all wondered why this happens. Thanks for any information that you can give me.


Work Gear for Electricians and the Trades

#43329 - 10/10/04 10:18 PM Re: nuetral question  
Wirenuttt  Offline
Member
Joined: Nov 2002
Posts: 267
Massachusetts
First thing that comes to mind is unbalanced load. Second, the old edison wiring method on 3-ph systems where they shared 3 hots of a, b & c phase and used one nuetral.


#43330 - 10/10/04 10:44 PM Re: nuetral question  
frenchelectrican  Offline
Member
Joined: Feb 2003
Posts: 939
Wi/ Paris France { France for ...
the same thing with multicircuit single phase also when someone is not too bright with L-N-L set up and when the load get uneven it will actally over heat too and once a while i will see the diy's do put the breaker on wrong leg and end up burn the netural wire pretty bad i did see it happend few places it is no fun to fix it right


merci, marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)


#43331 - 10/11/04 02:09 AM Re: nuetral question  
Trumpy  Offline


Member
Joined: Jul 2002
Posts: 8,211
SI,New Zealand
Quote
First thing that comes to mind is unbalanced load.

I'd second that!. [Linked Image]
Neutrals in 3 phase wye systems carry the (usually minimal) out-of-balance current and unless there is a gross imbalance of the loads, shouldn't usually be a problem.
However, one situation where I have seen a Neutral get so hot the PVC insulation melted off it, was where an Electrician used a Neutral that was only half the size that it should have been, in a 3wire 230 system over here. [Linked Image]

[This message has been edited by Trumpy (edited 10-11-2004).]


Let's face it, these days if you're not young, you're old - Red Green grin

#43332 - 10/11/04 06:17 AM Re: nuetral question  
SteveMc  Offline
Member
Joined: Feb 2004
Posts: 62
Rock Hill, SC
Computers and other non-linear loads add to neutral overheating. any circuit that will have a lot of electronics need it own neutral. The other problem that I have found is loose connections at the neutral bar due to more than one wire under the screw.


#43333 - 10/11/04 10:49 AM Re: nuetral question  
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
Quote
Computers and other non-linear loads add to neutral overheating.

Only on three phase wye systems. The neutral problem with nonlinear loads does not happen on single phase 120/240 volt three wire systems.
Don


Don(resqcapt19)

#43334 - 10/11/04 10:12 PM Re: nuetral question  
Norstarr  Offline
Member
Joined: Sep 2004
Posts: 86
Wi
You will usually find this situation when someone has relocated breakers in a panel and now have both circuits on a three wire circuit on the same leg in the panel. Instead of the neutral carrying the difference between the two circuits now it is additive. If you have two 20 amp breakers the neutral could concievably carry 40 amps, hence the burnt or discolored neutral wire. And as Stevemc stated, it is caused by loose connections at the neutral bar. I make it a habit that whenever I open a customers panel I tighten all connections. Takes a minute and if they are there it leaves an impression.
Ron



Member Spotlight
BEAMEUP
BEAMEUP
WA
Posts: 27
Joined: December 2004
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.012s Queries: 14 (0.002s) Memory: 0.7832 MB (Peak: 0.9371 MB) Zlib enabled. Server Time: 2017-03-25 01:58:41 UTC