Phase Coloring

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I have ran into this several times lately. A Small - Medium commercial building customer wants an upgrade from 1? to 3? (usually just for a piece of equipment or two). Last time was an old two story building bought by a lawyer. GC added a 3? elevator and the A/C guy installed 3? units. It was much cheaper to go Delta. POCO will add the HIGH leg for no cost, but will charge big bucks for 120/208 WYE.

I use Black & Blue because Red is "B" ? to me and it looks to much like Orange when it is faded.
 
TOMWELDS said:
...it seems to read as if its physically impossible to get 3phase from a wye system..
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Obviously, that's incorrect; it's the voltages you're having difficulty with. In a Y system, the phase-to-phase voltage is less than twice the phase-to-neutral voltage, but all three phase-to-neutral voltages are the same.

In a Delta system, the phase-to-neutral voltage on the two non-high-leg phases is half of the phase-to-phase voltage, exactly like the single-phase 240/120v system in your house; the phase-to-neutral voltage on the high leg is, well, higher.

Either system can feed 3-phase loads as long as the voltage suits the load, whether 208v or 240v. All three phases on a Y system can feed line-to-neutral loads, but only the two non-high-leg phases on a Delta system can.
 
Minuteman said:
I use Black & Blue because Red is "B" ? to me and it looks to much like Orange when it is faded.
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That was kinda my thinking too. I built a 3 phase service on a power pole for a residential customer a while back and had Black, Blue, Orange from left to right.

Hopefully, the fellow who came along behind me to remove the temp and install the disconnect on the structure itself didn't copy me from the service, and instead moved the high-leg to the center lug of his panel, Black, Orange, Blue. I never saw the end result.
 
On a 120/240 three phase Delta system I like using Pink, Orange and Purple as the color code.

The reason I use these colors is because they explain what will happen should the 208 high leg get used to feed a 120 volt piece of equipment, POP.

Now doesn?t that make a lot more sense than some of them other color combinations that are being used around the world today?
 
You can identify the conductors with any color, excepting the high leg.
GC is white or gray. What ever colors you choose must be posted on each branch circuit panelboard
 
Minuteman said:
I use Black & Blue because Red is "B" ? to me and it looks to much like Orange when it is faded.
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What ? Red is to me was not the concern. It was the maintenance guy that will be told to add say a 240V, 1?, 3W twist-lok receptacle to the side of the control panel for addon processing equipment, at some point in the future. As you can surmise, their are many weekend electricians familiar with the concept of 1?, 3W being Black, White, and Red. Not too many can conceptualize, especially when not saavy enough to check with a meter, that faced with the choice of Black, Orange, Blue, and White the receptacle would use Black, White, and Blue (or would that be Orange :D ).

Obviously, I cannot say either one of us is right. Just some food for thought...
 
Smart$, in your scenario the person that would have made this mistake should not have been working on this system with out supervision.

See the definition of "Qualified Person"

In my few years in this trade I have seen the High leg landed in every position and marked Blue, Red, Purple, and of course Orange at one time or another.

Roger
 
roger said:
Smart$, in your scenario the person that would have made this mistake should not have been working on this system with out supervision.

See the definition of "Qualified Person"
Roger
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I do not disagree with you, or any [noteworthy] comment. However, it is the unqualified person that does not read, let alone understand the NEC. Even as qualified persons, it is impossible for us to make our installations idiot proof, but if it saves one life, something as little as the color of a short piece of tape is worth it...!!!
 
Smart $ said:
I do not disagree with you, or any [noteworthy] comment. However, it is the unqualified person that does not read, let alone understand the NEC. Even as qualified persons, it is impossible for us to make our installations idiot proof, but if it saves one life, something as little as the color of a short piece of tape is worth it...!!!
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Smart$, I agree with you. From henceforth, I will never, ever, ever put blue phase tape on a the C? of a 240volt Delta, as I would not be able to live with myself should it cause some unqualified person or under-qualified person harm.

There, now I can sleep tonight.
 
From the San Francisco Code:
(1) 120/240 volt 3-wire circuits - ?A? phase black, ?B? phase red; 120/208 volt 4-wire 3-phase wye circuits - ?A? phase black, ?B? phase red, ?C? phase blue; 120/240 volt 3-phase delta circuits - ?A? phase black, ?B? (high leg) phase purple, ?C? phase red; 277/480 volt 4-wire 3-phase wye circuits - ?A? phase brown, ?B? phase orange, ?C? phase yellow; ungrounded conductors for other voltages shall be identified by different color coding, marking tape, tagging, or other approved means.
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Why PURPLE? Well, it's San Francisco, right?
 
e57 said:
From the San Francisco Code:
[/b]

Why PURPLE? Well, it's San Francisco, right?
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Our local POCO requires purple also. We use purple at the weather head to the line side of the meter and orange on the load side to the panel.
 
Minuteman said:
Smart$, I agree with you. From henceforth, I will never, ever, ever put blue phase tape on a the C? of a 240volt Delta,
There, now I can sleep tonight.
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Michael and Smart$, if you were to go into older industrial plants and change the high leg color standard from blue or red to orange, you may very well cause a death or injury just as quick as not doing anything. If management allows unqualified people to do the work, colors won't make any difference.

Read 110.15 and 230.56 very closely to see if orange is really mandated.

The articles actually give better options of identification IMO.

Mark, I've never been to SF, but I have seen the purple high leg in more than one place here on the east coast, may have been some one who traveled between the east and west coasts who did these installations. :)

Roger
 
roger said:
Read 110.15 and 230.56 very closely to see if orange is really mandated.

The articles actually give better options of identification IMO.
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Can you elaborate? I see it as requiring the high leg to be marked orange (local amendments aside). You seem to indicate it's not...?
 
Smart $ said:
Even as qualified persons, it is impossible for us to make our installations idiot proof, but if it saves one life, something as little as the color of a short piece of tape is worth it...!!!
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I am trying to figure out how a misunderstood or missing hi-leg marking could lead to a death?
 
George, as Iwire points out, see the "or".

Roger
 
Minuteman said:
I use Black & Blue because Red is "B" ? to me and it looks to much like Orange when it is faded.
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The discussion that Smart $ and I were in was not regarding the High leg, but rather or not to mark the other two Black & Red or Black & Blue. We both seem to agree that the High leg ("B" ?) should be Orange.
 
Michael, why would marking these phases different colors be necessary, or I guess a better question would be, why would it be more likely to cause harm to some unqualified person if they weren't marked? These two conductors have the same voltage and associated dangers.


The high leg and grounded conductor are the only conductors in this system required to be identified.

Roger
 
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