Color coding three phase branch circuits

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electrofelon

electrofelon

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Location
Cherry Valley NY, Seattle, WA
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Electrician
Ok consider your typical commercial job with EMT home runs with MWBC's branching off to MC down to receps and other outlets. Typically I would put 3 #12 full boats in a 3/4 EMT. Lets just say its standard 120/208 and the only electrical system in the building, so there is no requirement to code the phases. Or course most common is to use black red blue, phase A,B,C respectively and this is pretty much what I have always done, however I am beginning to question this. Although the colors help a bit keeping track of things during the pull, it seems pointless and a hassle otherwise. Things never work out perfect so after some balancing, changes/additions, moving things around, a few screw ups - its never perfect in the panel. How crazy do you go trying to keep black A, Red B, Blue C?

What does the group think about this idea: Use the same color for each MWBC. For example if I am pulling 3 full boats, one of the boats is all black, another is all red, and the last is all blue? Doesnt that make a lot more sense? Seems like you care more about the boat number and which conductors are in it rather than which phase a given conductor is on.
 
So you'd pull one full boat with 3 blacks and a white?

That means you need 3 spools of black. If you're going to spool up 3 hots on the rack, make 'em different colors.

Lemme ask this: Suppose you've got a 3-ph load like a motor. Are you going to pull 3 blacks, then monkey around with phasing them to make sure your rotation is correct?
 
480sparky said:
So you'd pull one full boat with 3 blacks and a white?



That means you need 3 spools of black. If you're going to spool up 3 hots on the rack, make 'em different colors.
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Three full boats total: BLK,BLK,BLK,W R,R,R,W BLU,Blu,Blu,W. Ur gunna need the same number of spools no matter how ya do it.

Lemme ask this: Suppose you've got a 3-ph load like a motor. Are you going to pull 3 blacks, then monkey around with phasing them to make sure your rotation is correct?
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Ok, but how does BLK,R,BLu make it any different? ITs still guess and buy gosh.
 
electrofelon said:
Three full boats total: BLK,BLK,BLK,W R,R,R,W BLU,Blu,Blu,W. Ur gunna need the same number of spools no matter how ya do it.
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I like the idea although for your average MWBC I'd still use BK, RD, BL, W x 3 for my homeruns because it's easier to keep track of the phases when you start branching out to separate j boxes in conduit runs.

Now for specific runs, like your motor example, absolutely. I've done it that way and prefer it. Motor 1 all black, motor 2 all blue, lights, plugs all red.....

Another time I like to use the same colour on phases is doing all the line side conductors in one color and load in a different.

Ok, but how does BLK,R,BLu make it any different? ITs still guess and buy gosh.
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I agree. I don't know what he's talking about.
 
I always made the effort to keep black wires on A phase, red wires on B phase and blue wires on C phase. I did not find it very difficult if I mentally prepared for work. I think it's well worth the effort, and shows pride in work.
 
electrofelon said:
What does the group think about this idea: Use the same color for each MWBC. For example if I am pulling 3 full boats, one of the boats is all black, another is all red, and the last is all blue? Doesnt that make a lot more sense? Seems like you care more about the boat number and which conductors are in it rather than which phase a given conductor is on.
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So for example your black circuits would be 1,3,5, the reds 7,9,11 the blues 13,15,17. It's a bit unconventional but it would work. Personally I wouldn't want to see that when I opened the panel.
 
electrofelon said:
Yeah you hook it up, see if it's right, if not swap two phases. What am I missing? There might be a few times you know the rotation you want, but hardly ever in my experience.
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You've never run across a machine that will cost you hundreds of thousands if you happen to run the motor backwards?
 
electrofelon said:
Yeah you hook it up, see if it's right, if not swap two phases. What am I missing? There might be a few times you know the rotation you want, but hardly ever in my experience.
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Absolutely, it could be hooked up A B C, and still run backwards because utilities do not always bring it into the service as A B C, I was connecting generators on a healthcare facility campus in North Carolina after a hurricane, two services were C B A, one was A B C.
 
I agree there is no guarantee that if you follow Black, Red, Blue that the motor will run in the correct direction.
 
We have a color chart on our wire pulling cart. 1 thru 60 odd numbers on the left even on the right. Colors in the middle. Blk R Blu - Br- O- Ye.
We still can get it messed up. But only when the guys are running low on wire. We always keep it right in the panel
 
ActionDave said:
I like the idea although for your average MWBC I'd still use BK, RD, BL, W x 3 for my homeruns because it's easier to keep track of the phases when you start branching out to separate j boxes in conduit runs.
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Seems almost easier with each boat all equal color though. Ok so say I have pulled my three boats, 12 conductors. Now I need to cut or pull out say phase A of the red boat. Obviously its one of the three reds. With the traditional way, it would be one of the three blacks. With my way I could just pick a red, and ring it out later but at least it's the correct boat which is most important.
 
oldsparky52 said:
I always made the effort to keep black wires on A phase, red wires on B phase and blue wires on C phase. I did not find it very difficult if I mentally prepared for work. I think it's well worth the effort, and shows pride in work.
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I agree I'm quite anal about neatness and consistency, but other than the pretty visual, what does this black phase A, red phase B, blue phase C get you? It's pretty much pointless for most situations. Besides when you branch off to MC, none of that will be color coded. To me color coding is mostly for helping keep track of things during pulling, and again knowing which conductors are in a given boat seems to be the primary thing you want to know.
 
Where there is only one voltage system, you can do it any why you want to. There is no requirement to identify by phase. I think having the system as suggest would be much more difficult to work with when troubleshooting in the future.
 
don_resqcapt19 said:
Where there is only one voltage system, you can do it any why you want to. There is no requirement to identify by phase. I think having the system as suggest would be much more difficult to work with when troubleshooting in the future.
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Don, good point on future trouble shooting. Give me an example of how it trouble shooting would be easier traditional versus my way.
 
I don't see the gain doing it with your alternative method.

Typically, we'll pull in blk red blue w and you wrap the wires with white tape and label it 2-4-6, etc.

Your method, with pulling in all reds, blks, etc, you need to number each red, blk, etc individually at both ends to identify or you have to ring them out.

I just don't see the gain over blk rd blue utilizing common electrical practices. I also don't understand why circuits would move around in an office panel, if you install a panel with extra spaces for future?
 
electrofelon said:
Three full boats total: BLK,BLK,BLK,W R,R,R,W BLU,Blu,Blu,W. Ur gunna need the same number of spools no matter how ya do it.



Ok, but how does BLK,R,BLu make it any different? ITs still guess and buy gosh.
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I have done three, three and three many times, especially with multiple three phase motor circuits in same run. If you wanted BRB to each motor then you still need to further identify for each individual circuit.

Most the motors I typically connect won't harm anything if they run wrong direction briefly when first connecting them. If you have a dozen motors on a feeder and 3/4 of them are wrong direction when first energizing then you reverse the feeder phasing and then reverse the other three individually, can be done at the breaker, at the controller, at the motor, at the motor disconnect - lots of options some pretty easy.

If your driven load absolutely can not be run in reverse direction at all, not even a quick "bump" for testing, then you really need to uncouple load and test it that way to be certain IMO Even if you used a rotation meter, you can still make a mistake.

Code only requires this identification when there is more than one voltage system present. I see some benefit of identifying voltage system, most the time really don't care about identifying phase other than a high leg if you have one. There can be times however where it maybe can be important, but nothing wrong with leaving that as a design decision either.
 
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