The Electrical Contractor Network

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

Books, Tools and Test Equipment for Electrical and Construction Trades

Topic Options
Rate This Topic
#26636 - 06/17/03 04:48 PM History of the colors
Steve Miller Offline
Member
Registered: 08/30/01
Posts: 322
Loc: Loudoun Cty, VA
Does anybody know how we (the industry) decided that the primary phase colors should be BK-RD-BL for 208Y120 and BR-OG-YL for 480Y277? Any historical or code help would be appreciated since I have no clue other than to say "It's always been that way, it's tradition"
Top
Work Gear for Electricians and the Trades
#26637 - 06/17/03 05:08 PM Re: History of the colors
BrianSparky Offline
Member
Registered: 01/06/02
Posts: 38
Loc: Lakewood,CO
Hi Steve,
This is only hearsay, but I heard that the Brown, Orange, Yellow for 480 was decided on because it makes an easly remembered acronym BOY, so that electricians could remember the sequence when phasing out the wires.

Who knows?
Top
#26638 - 06/17/03 06:17 PM Re: History of the colors
Bill Addiss Offline
Member
Registered: 10/07/00
Posts: 4196
Loc: NY, USA
FWIW, On Long Island we use the same colors for 208Y120 in another variation of the same order - Blue/Black/Red

I guess we just like to be different?


Bill
Top
#26639 - 06/17/03 10:04 PM Re: History of the colors
Bjarney Offline
Moderator
Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Bill, the province of Alberta and Western Area Power Administration {a federal bulk-power utility} use Red/Black/Blue for 208Y ‘ABC-123’ phasing

There are a number of institutional facilities that publish their “Division 16” (electrical) design standards online.

I learned Brown-Violet-Yellow {Gray} for 480Y/277V phasing in the 1970s.

ucdavis.edu wsu.edu ohio-state.edu and others list the “B-O-Y” 480V code for ‘ABC-123’ phasing.

stanford.edu lists 277/480V 3P 4W… normally Brown, Purple or Orange, Yellow, Gray or White, as does GE metering-retrofit instructions.

berkeley.edu {and sister facilities} list Brown, Yellow, Purple, and White for 480Y/277V systems, as does ci.brisbane.ca.us. Aside—“B-Y-P” in Berkeley evolved from their 1950s standard of Black-Yellow-Green(!) for 480V ∆ systems. Bare copper was the mandatory equipment-grounding conductor within all raceways and enclosures—metal or otherwise. [Green-jacketed grounding conductors are now permitted, but there is tons of existing gear with bare equpemnt grounds.]

The Omaha 480Y/277V utility network ABC-123 phasing is Brown, Orange and Purple in their standards.

Lithonia Lighting shows Yellow-Brown-Orange-White for 480Y/277V.

Last but not least, the City of San Francisco calls out Black-Violet-Blue for 240V 4W∆, to not conflict with the 480V B-O-Y code. Many others use Black-Orange-Blue for 240V 4W∆.
Top
#26640 - 06/18/03 12:36 AM Re: History of the colors
pauluk Offline
Member
Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
The choice of colors, and how they've changed over the years always fascinates me.

Just how common was it for green to be designated a phase in the past? Was this a "Berkeley special," or did other places use it as well?
Top

Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box

Recent Posts
Looking for older post
by sparkyinak
Today at 12:27 AM
License exam
by TRUE POWER
Yesterday at 11:33 PM
Members: Non-Members: Did you know?
by Admin
Yesterday at 02:34 PM
Safety at heights?
by HotLine1
01/21/17 08:51 PM
International Wire Colour Codes
by Texas_Ranger
01/21/17 03:29 PM

Who's Online
0 registered (), 69 Guests and 10 Spiders online.
Key: Admin, Global Mod, Mod
New in the Gallery:
Desk-mounted "power-board"
Top Posters
gfretwell 9066
Trumpy 8560
pauluk 7693
HotLine1 6833
sparky 5545
Member Spotlight
Tom
Tom
Member Since: 01/01/01
Posts: 1069

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals