Different voltage systems in same building

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At present there are 3 different systems in this building, 208/120 3ph , 480/277 3ph, and 240/120 single ph. Most of the 120/208 has used the black red blue color code, and the 277/480 has used the brown orange yellow colors. Coworker has stated that we cannot use the black red blue again for the 120/240 system that has been installed.

What colors would you use for this system? is it even required like he said? I don't have my code book in front of me right now, but I do know we have to have a somewhat of a different color scheme going, but I thought it had mostly to do with the voltage per se.
 

iwire

Moderator
Staff member
Location
Massachusetts
At present there are 3 different systems in this building, 208/120 3ph , 480/277 3ph, and 240/120 single ph. Most of the 120/208 has used the black red blue color code, and the 277/480 has used the brown orange yellow colors. Coworker has stated that we cannot use the black red blue again for the 120/240 system that has been installed.

What colors would you use for this system? is it even required like he said? I don't have my code book in front of me right now, but I do know we have to have a somewhat of a different color scheme going, but I thought it had mostly to do with the voltage per se.

Each voltage system must be identified, how it's done is up to the installer, colors are a common way but not a required way.

The method chosen must be posted.
 

iwire

Moderator
Staff member
Location
Massachusetts
Here are some 2014 code sections

215.12 Identification for Feeders.

(1) Feeders Supplied from More Than One Nominal
Voltage System. Where the premises wiring system has
feeders supplied from more than one nominal voltage system,
each ungrounded conductor of a feeder shall be identified
by phase or line and system at all termination, connection,
and splice points in compliance with
21S.12(C)(l)(a) and (h).

(a) Means of Identification. The means of identification
shall be permitted to be by separate color coding, marking
tape, tagging, or other approved means.

(b) Posting of Identification Means. The method utilized
for conductors originating within each feeder panelboard
or similar feeder distribution equipment shall be
documented in a manner that is readily available or shall be
permanently posted at each feeder panelboard or similar
feeder distribution equipment.




210.5 Identification for Branch Circuits.

(1) Branch Circuits· Supplied from More Than One
Nominal Voltage System. Where the premises wiring system
has branch circuits supplied from more than one nominal
voltage system, each ungrounded conductor of a branch
circuit shall be identified by phase or line and system at all
termination, connection, and splice points in compliance
with 210.5(C)(1)(a) and (b).

(a) Means of Identification. The means of identification
shall be permitted to be by separate color coding, marking
tape, tagging, or other approved means.

(b) Posting of Identification Means. The method utilized
for conductors originating within each branch-circuit
panelboard or similar branch-circuit distribution equipment
shall be documented in a manner that is readily available or
shall be permanently posted at each branch-circuit pane]board
or similar branch-circuit distribution equipment.
 

ADub

Senior Member
Location
Midwest
Occupation
Estimator/Project Manager
At present there are 3 different systems in this building, 208/120 3ph , 480/277 3ph, and 240/120 single ph. Most of the 120/208 has used the black red blue color code, and the 277/480 has used the brown orange yellow colors. Coworker has stated that we cannot use the black red blue again for the 120/240 system that has been installed.

What colors would you use for this system? is it even required like he said? I don't have my code book in front of me right now, but I do know we have to have a somewhat of a different color scheme going, but I thought it had mostly to do with the voltage per se.

That's getting pretty picky. Use the black and red scheme for you 120/240 single phase and forget about it. If you think someone will have trouble recognizing it just write the system specs and origin on the box lids like you should be anyway


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iwire

Moderator
Staff member
Location
Massachusetts
That's getting pretty picky. Use the black and red scheme for you 120/240 single phase and forget about it.

If black and red have already been designated as the identification means of the 208Y/120 system it would be an NEC violation to use them as the identification means of the 120/240 system.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
If black and red have already been designated as the identification means of the 208Y/120 system it would be an NEC violation to use them as the identification means of the 120/240 system.

That doesn't leave many other colors, maybe pink and violet with a white or gray neutral with a tracer?
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Why not back - black - white? Polarity/rotation is not an issue with single phase wiring.
 

iwire

Moderator
Staff member
Location
Massachusetts
Why not back - black - white? Polarity/rotation is not an issue with single phase wiring.

Black has been already used on the 208 volt system and ...


Where the premises wiring system has
feeders supplied from more than one nominal voltage system,
each ungrounded conductor of a feeder shall be identified
by phase or line
 

big john

Senior Member
Location
Portland, ME
In the past I've handled this with dual colors. For the example:

All 120/208 was black/red/blue.

And all 347/600 was black-orange/red-orange/blue-orange.
 

Smart $

Esteemed Member
Location
Ohio
In the past I've handled this with dual colors. For the example:

All 120/208 was black/red/blue.

And all 347/600 was black-orange/red-orange/blue-orange.
Black (solid) is not the same as black-orange (i.e. black with orange tracer)...

...but that's the smart way to use similar colors, as long as you know it going in.
 

Smart $

Esteemed Member
Location
Ohio
Having to identify at each access point, one can simply use phase tape grouping of one (or both) systems with a black conductor. For example, band all 120/240V 1Ø wiring* with purple phase tape.

* Circuit wires as a whole, not each individual wire.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Black has been already used on the 208 volt system and ...
I didn't think that every conductor had to be different, just the voltages. If 208 3P4W is red/blue/black with a white neutral and 240 1P3W is two blacks with a white neutral, then any time you see a black and a white it's 120V.
 

big john

Senior Member
Location
Portland, ME
I didn't think that every conductor had to be different, just the voltages. If 208 3P4W is red/blue/black with a white neutral and 240 1P3W is two blacks with a white neutral, then any time you see a black and a white it's 120V.
There's no prohibition on mixing voltages in a raceway or junction, so in a box with two blacks, a blue, and a white, which black goes to which system? That's why you need unique identifiers.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
There's no prohibition on mixing voltages in a raceway or junction, so in a box with two blacks, a blue, and a white, which black goes to which system? That's why you need unique identifiers.
Point.
 

ADub

Senior Member
Location
Midwest
Occupation
Estimator/Project Manager
If black and red have already been designated as the identification means of the 208Y/120 system it would be an NEC violation to use them as the identification means of the 120/240 system.

Oh I'm aware and I stand by my first comment. This isn't even worth discussion in most venues but it is MH after all


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iwire

Moderator
Staff member
Location
Massachusetts
Oh I'm aware and I stand by my first comment.

OK using your own words ... :D

You're wrong. Have you ever read 250.64(E)(1)? Do you know what ferrous means? You probably shouldn't speak in absolutes unless you're positive you know your subject matter.

Just change 250.64 for 210.5 or 215.12 and ferrous for identification. :p



This isn't even worth discussion in most venues but it is MH after all

Strange, I assumed the OP wanted a code answer not a 'What does ADub get away wih answer' but I must have been wrong.
 

peter d

Senior Member
Location
New England
As an aside, in Canada they use black, red and blue for everything no matter what the voltage system is. I believe they also have separation requirements too (347 volts cannot share the same raceway as 120 volts, unlike the NEC.) Anyway, I like that in the sense it requires the electrician to test and not assume voltage level based on the color of the wire.
 
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