ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
sparky 4
Recent Posts
Dimmable LED 2x4 lay in fixtures
by gfretwell. 12/13/17 09:49 PM
2017 NEC Changes
by sparky. 12/13/17 06:57 PM
Casino Wiring methods
by HotLine1. 12/09/17 10:44 AM
Ground wire Size to water Line.
by HotLine1. 12/05/17 12:11 PM
Flexible conduit to an outside Spa
by gfretwell. 12/05/17 12:28 AM
New in the Gallery:
Gallery Test
Popular Topics(Views)
243,037 Are you busy
179,457 Re: Forum
170,395 Need opinion
Who's Online Now
0 registered members (), 14 guests, and 8 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#100401 - 11/16/06 06:03 PM Date of adoption?  
VAElec  Offline
Joined: Jul 2005
Posts: 49
Sterling, Virginia, US
Without tracking down previous editions of the code and referencing them, is anyone aware of a method to find out when a section of the code was adopted/amended? Example I saw today that brings this to mind: 3-phase 4-wire delta-connected panel. High leg was marked orange (good per NEC 384-3 (e) '99), but landed on C phase (bad per NEC 384-3 (f) '99). Don't know when the panel was installed but would say within the last 20-30 years. Was landing the high leg on anything but B phase ever acceptable (I'm sure it was at some point but that's that whole me assuming things problem). But the main question is when we are asked to “take a look at something” and it is to code but for one small thing, how do we figure out if it was acceptable at some point. I mean other than asking the question here.


2017 / 2014 NEC & Related Books and Study Guides

#100402 - 11/16/06 07:50 PM Re: Date of adoption?  
Tom  Offline
Joined: Jan 2001
Posts: 1,044
Shinnston, WV USA
I really don't know of any way of checking. I know that some utility companies require the high leg to be C phase in the meter. In the panelboards,

B phase gets the extra bracing so putting the high leg anywhere else could be a problem.

Looking at my oldest code book (1978) 384-3(f) "...The B phase shall be that phase having a higher voltage to ground."

Few things are harder to put up with than the annoyance of a good example.

#100403 - 11/16/06 10:26 PM Re: Date of adoption?  
ShockMe77  Offline
Joined: Jun 2005
Posts: 821
Rahway, New Jersey
I've come across existing installations where the high-leg is on the 'C' phase alot. I'll have to check my POCO specs book (PSE&G) and see if they're required like that around here. I know it's not what the NEC calls for, but most of the high-leg 3-phase services are identified with red tape, not orange.

#100404 - 11/17/06 10:25 AM Re: Date of adoption?  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Looking at my oldest code book (1978) 384-3(f) "...The B phase shall be that phase having a higher voltage to ground."

There's no 384-3(f) in the 1971 NEC, nor can I see any other applicable reference within article 384.

200-6(c) in 1971 covered general identification of the high-leg:

Where, on a 4-wire delta-connected secondary, the midpoint of one phase is grounded to supply lighting and similar loads, that phase conductor having the higher voltage to ground shall be orange in color or be indicated by tagging or other effective means at any point where a connection is to be made if the neutral conductor is present.

The part I've quoted bold has the "changed from previous edition" line alongside. I seem to recall a discussion a while back in which it was decided that 1971 was the first time orange was suggested specifically.

Still nothing about the high leg having to be B phase that I can find though.

Member Spotlight
Posts: 165
Joined: March 2007
Show All Member Profiles 

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.012s Queries: 14 (0.003s) Memory: 0.7619 MB (Peak: 0.8939 MB) Zlib enabled. Server Time: 2017-12-14 10:06:57 UTC