# 3 phase circuit numbering



## 480sparky

All multiples of 6 are C phase.

Those multiples -1 are also C phase.

Those multiples -2 and -3 are B phase.

Those multiples +1 and +2 are A phase.

36 is C phase, 36+1 (37) would be A.


----------



## Voltech

when I put my breakers in, i put a piece of white tape down one side and write the number on it. I also keep a chart on the wire cart and at the panel... Like this


----------



## mattsilkwood

480sparky said:


> All multiples of 6 are C phase.
> 
> Those multiples -1 are also C phase.
> 
> Those multiples -2 and -3 are B phase.
> 
> Those multiples +1 and +2 are A phase.
> 
> 36 is C phase, 36+1 (37) would be A.


 x2:thumbsup:


----------



## 480sparky

Voltech said:


> when I put my breakers in, i put a piece of white tape down one side and write the number on it. I also keep a chart on the wire cart and at the panel... Like this


Rats. I'm doing 277...........:laughing:


----------



## Toronto Sparky

Easier to just grow 42 fingers and just paint them.


----------



## Dennis Alwon

Toronto Sparky said:


> Easier to just grow 42 fingers and just paint them.


Yeah but then you have the new 60 circuit panels coming out.


----------



## wildleg

I put colors on the text on my ckt #'s on a panel sched I made in excel, so I print one out and stick on panel while roughing in and its brainless.

I was playing with excel last night, here's a formula for if you want to stick a number in a cell and have it tell you what phase (using cell A4)

=LOOKUP(MOD(A4,6),{0,1,2,3,4,5},{"A","A","B","B","C","C"})

somebody used to make a little card you keep in your pocket for that (like a cheater card for blackjack at the casinos)


----------



## sparks134

This guy made a nice little chart... :thumbup:http://www.sparkyuonline.com/Electrical-Wiring-Color-Chart.html


----------



## Toronto Sparky

sparks134 said:


> This guy made a nice little chart... :thumbup:http://www.sparkyuonline.com/Electrical-Wiring-Color-Chart.html



Black Red Blue?

Always been Red Black Blue here.. I just assumed it was that way almost everywhere... I stand Corrected..

http://en.wikipedia.org/wiki/Three-phase_electric_power


----------



## 480sparky

All those cheat sheets and cards and whatnot are fine.......... until you lose it or forget it.

Learn to calculate it, and you'll never use these cards & sheets again.


----------



## Toronto Sparky

Dennis Alwon said:


> Yeah but then you have the new 60 circuit panels coming out.


Guess I'm gonna have to get a job at the reactor.. :blink:


----------



## crazymurph

If it's divisible by 6 it's blue, and the one before it too.


----------



## JohnR

*Use your Tape measure*

I always just use my tape measure for panels that are series rated, has all the numbers there, and you only have to remember that 1,2 are phase A, 3,4 are phase B - 5,6 are phase C , etc... 

Just go to the area you are looking the color for, and start at the 1,2 closest using two fingers along the tape and move your way up/down till you hit the number that you want the color for. 

I almost always have a tape with me, but the little cards, might loose them.
I am too dumb:jester: to remember all that MATH involved with the other methods.

Around here, commercial colors are Brown Orange Yellow , even though the orange is really for the high-leg technically.


----------



## Elec-Tech

480sparky said:


> All multiples of 6 are C phase.
> 
> Those multiples -1 are also C phase.
> 
> Those multiples -2 and -3 are B phase.
> 
> Those multiples +1 and +2 are A phase.
> 
> 36 is C phase, 36+1 (37) would be A.





That is the best way right there.....


----------



## manchestersparky

anything divisable by 6 is "C" phase.
Like 480 posted.

Learn it and you will find it is easier and faster then those cheat sheets and what nots. More professional also. 

Everyone on the projects I ran could tell you the circuit color without a cheatsheet.


----------



## East Coast Newbie

Divide circuit number by 6 then use the remainder to identify the phase color.

Remainder 1 or 2 Red 
3 or 4 Black
5 or no remainder Blue


----------



## vasparky27

Thanks for the posts I had the same questions and am glad I found this site!


----------



## kaboler

crazymurph said:


> If it's divisible by 6 it's blue, and the one before it too.


That's the method I was taught.


----------



## kaboler

Toronto Sparky said:


> Black Red Blue?
> 
> Always been Red Black Blue here.. I just assumed it was that way almost everywhere... I stand Corrected..
> 
> http://en.wikipedia.org/wiki/Three-phase_electric_power


In Canada, it's Red Black Blue but I've caught electricans doing Brown Orange Yellow for 600v, and I tell them that it's only for "isolated circuits" though I don't know what an isolated circuit really is (for hospital use), unless it's some kind of long leg delta transformer setup where the long leg has to be marked Orange. Never worked with either. But it's in the codebook.


----------



## bobelectric

Today, Everything is Black And Gold!​


----------



## HARRY304E

480sparky said:


> Rats. I'm doing 277...........:laughing:


277 /480volts.http://www.sparkyuonline.com/Electrical-Wiring-Color-Chart.html


----------



## Toronto Sparky

I always liked those light pink or grey neutrals they were shipping a few years ago..


----------



## electrolover

Zaped said:


> I would welcome any reference to where online I may find the 'forumula'/shortcut for determing the phase color of a given circuit number in a 3 phase panel (without having to count through the colors on my fingers starting from breaker 1 or 2). For example, what would the phase color be of circuit #37. Thanks.



i do it by division which is pretty much the same thing as every one else.

divide by 6, if the remainder is 1or2 its black(a) 3or4 its red(b) 5or0 its blue(c). it helps to memorize you 6 tables because all you really need is the remainder

there is nothing more aggravating than getting a helper who has to pull out a sheet or tape measure every time he has to pull a wire.
besides if your pulling into a 3 section panel that sheet wont help ya.
if you practice you should know any color with out pause in a short time


----------



## electrolover

sometimes depending on the city its brown PURPLE yellow.
weird huh?


----------



## 480sparky

electrolover said:


> sometimes depending on the city its brown PURPLE yellow.
> weird huh?



Only if it's a legally-adopted amendment.


----------



## electrolover

its mainly in austin from what i here but i have been on jobs in mckinney and allen that had purple. its not too uncommon here i guess, every one has at least heard of it


----------



## kaboler

http://www.sparkyuonline.com/images/wire%20color%20chart%20brb.png

Bah, it's RED BLACK BLUE. No wonder everyone worries so much about blue, because it seems black and red vary by region to region. And I've seen BOY and OBY before, but it's Red Black Blue in Canada regardless of voltage.


----------



## Nildogg

i


Elec-Tech said:


> That is the best way right there.....


 
I think I might be stupid, but am I stupid?

3x+1=A
3X-1=B
3x=C


----------



## mattsilkwood

electrolover said:


> its mainly in austin from what i here but i have been on jobs in mckinney and allen that had purple. its not too uncommon here i guess, every one has at least heard of it


 There's a little town about 10 minutes south of Sugarland that's brown, purple, yellow too.


----------



## 480sparky

Nildogg said:


> i
> 
> 
> I think I might be stupid, but am I stupid?
> 
> 3x+1=A
> 3X-1=B
> 3x=C




You're missing 3 other equations, so it's really a 50% score.

3x=C
3X-1=C

3X+1=A
3X+2=A

3X+3=B
3X+4=B


----------



## Nildogg

480sparky said:


> You're missing 3 other equations, so it's really a 50% score.
> 
> 3x=C
> 3X-1=C
> 
> 3X+1=A
> 3X+2=A
> 
> 3X+3=B
> 3X+4=B


 
That doesn't work either.

6x=C
6X-1=C

6X+1=A
6X+2=A

6X+ or -3=B
6X-2=B


----------



## Toronto Sparky

Keep it simple.. Use only black wire... but make every forth white


----------



## HARRY304E

Toronto Sparky said:


> Keep it simple.. Use only black wire... but make every forth white


 I say just black wire for every thing..:laughing::laughing:


----------



## 480sparky

Nildogg said:


> That doesn't work either.
> 
> 6x=C
> 6X-1=C
> 
> 6X+1=A
> 6X+2=A
> 
> 6X+ or -3=B
> 6X-2=B



Correct you are. I saw the 3's, and simply repeated them.


----------



## Smoke

Zaped said:


> I would welcome any reference to where online I may find the 'forumula'/shortcut for determing the phase color of a given circuit number in a 3 phase panel (without having to count through the colors on my fingers starting from breaker 1 or 2). For example, what would the phase color be of circuit #37. Thanks.


it depends on where you live, if in the US Sparky is spot on.
you would be surprised how many dont know it.
any number divisible by 6 is blue or yellow, the number before it is also yellow or blue.
commercial electricians frequently need to be gud at math, if your not yo may want to rethink your choices. just my opinion

Smoke


----------



## 480sparky

Smoke said:


> .........
> any number divisible by 6 is blue or yellow,.........



Any number divisible by 6 is the C phase. What color the conductor used for that phase could be anything except white, gray or green.


----------



## Smoke

480sparky said:


> Any number divisible by 6 is the C phase. What color the conductor used for that phase could be anything except white, gray or green.


exactly, i just assumed they may want to use the proper color sequence lol

if we were to get technical, i have used sq-d panels where "6" for instance is "a" phase. there are a few exceptions to the 6 method.

btw, in germany blue is the neutral.


----------



## nitro71

Once again I'm going to say that some of us aren't pulling wire and labeling three phase panels every day and like to have a cheat sheet with us.


----------



## jawnybee

*phase colors*

I figured out an easy way to calculate phase colors so here it us. An easy way to remember it us to remember a little rhyme. ”black, red, blue. One, zero, two. Black and one represents phase one. Red and zero represent phase two and blue and two represents pad three. The numbers reefer to the remainder. 

The way to calculate is to take any breaker number and decide by 3. What makes this formula so easy is that when you have a2 digit breaker number you just add the two numbers together and then decide by three. You're always using low numbers to devide.

For instance, take breaker # 43. Add 4 + 3 = 7. Devide by 3 and you have a remainder of 1. That means the phase color will be black. Now if the breaker is an even # just drop down one # to calculate. For instance, breaker #44 is on the same leg as breaker #43 so drop down from breaker #44 to breaker #43 and calculate.

Here are more examples; breaker # 23. (2+3=5 devide by 3 has a remainder of 2 thus ”black red blue, 1, 0, 2. The phase is blue.

Breaker #36, because its an even # you drop one down to breaker #35 (because they are on the same phase leg in the panel). 3+5=8 devide by 3 and has a remainder of 2
Black, red, blue. 1, 0,2. The phase is blue.

Breaker #13. 1+3=4/3 remander of 1. That would be phase 1 or black.

It is kind of confusing st first but I think out is the fastest calculation once you learn the method. I have taught this method to a few electricians who now use it.

Please let me know if this had been helpful.


----------



## jawnybee

*phase colors (resubmitted because of type o's*

I figured out an easy way to calculate phase colors so here it us. An easy way to remember it us to remember a little rhyme. ”black, red, blue. One, zero, two. Black and one represents phase one. Red and zero represent phase two and blue and two represents phase three. The numbers refer to the remainder. 

The way to calculate is to take any breaker number and devide by 3. What makes this formula so easy is that when you have a 2 digit breaker number you just add the two numbers together and then devide by three. You're always using low numbers to devide.

For instance, take breaker # 43. Add 4 + 3 = 7. Devide by 3 and you have a remainder of 1. That means the phase color will be black. Now if the breaker is an even # just drop down one # to calculate. For instance, breaker #44 is on the same leg as breaker #43 so drop down from breaker #44 to breaker #43 and calculate.

Here are more examples; breaker # 23. (2+3=5 devide by 3 has a remainder of 2 thus ”black red blue, 1, 0, 2. The phase is blue.

Breaker #36, because its an even # you drop one down to breaker #35 (because they are on the same phase leg in the panel). 3+5=8 devide by 3 and has a remainder of 2
Black, red, blue. 1, 0,2. The phase is blue.

Breaker #13. 1+3=4/3 remander of 1. That would be phase 1 or black.

Breaker #27. 2+7=9/3 remainder 0 phase 2 (or red)

It is kind of confusing at first but I think it is the fastest calculation once you learn the method. I have taught this method to a few electricians who now use it.

Please let me know if this has been helpful.


----------



## 360max

Voltech said:


> when I put my breakers in, i put a piece of white tape down one side and write the number on it. I also keep a chart on the wire cart and at the panel... Like this


thats only if the phasing in the panels is black, red, blue


----------



## 360max

jawnybee said:


> I figured out an easy way to calculate phase colors so here it us. An easy way to remember it us to remember a little rhyme. ”black, red, blue. One, zero, two. Black and one represents phase one. Red and zero represent phase two and blue and two represents phase three. The numbers refer to the remainder.
> 
> The way to calculate is to take any breaker number and devide by 3. What makes this formula so easy is that when you have a 2 digit breaker number you just add the two numbers together and then devide by three. You're always using low numbers to devide.
> 
> For instance, take breaker # 43. Add 4 + 3 = 7. Devide by 3 and you have a remainder of 1. That means the phase color will be black. Now if the breaker is an even # just drop down one # to calculate. For instance, breaker #44 is on the same leg as breaker #43 so drop down from breaker #44 to breaker #43 and calculate.
> 
> Here are more examples; breaker # 23. (2+3=5 devide by 3 has a remainder of 2 thus ”black red blue, 1, 0, 2. The phase is blue.
> 
> Breaker #36, because its an even # you drop one down to breaker #35 (because they are on the same phase leg in the panel). 3+5=8 devide by 3 and has a remainder of 2
> Black, red, blue. 1, 0,2. The phase is blue.
> 
> Breaker #13. 1+3=4/3 remander of 1. That would be phase 1 or black.
> 
> Breaker #27. 2+7=9/3 remainder 0 phase 2 (or red)
> 
> It is kind of confusing at first but I think it is the fastest calculation once you learn the method. I have taught this method to a few electricians who now use it.
> 
> Please let me know if this has been helpful.


that does not work on all types of panels, some have different phase colors on opposite side of these 'weirdo' panels (Industrial Panels), I think they are square d. Its a bus duct run down the middle of the panel and breakers plug into it. On odd side of panel phasing starts a,b,c but on even side it starts c,b,a. Just checked its the Square D- I Line Panels


----------



## michaelalbrecht

Zaped said:


> I would welcome any reference to where online I may find the 'forumula'/shortcut for determing the phase color of a given circuit number in a 3 phase panel (without having to count through the colors on my fingers starting from breaker 1 or 2). For example, what would the phase color be of circuit #37. Thanks.


 divide by 6 37 divided by 6 is 6 with a remainder of one 1 is black that is your color


----------



## Toronto Sparky

Red , Black , Blue in Canada


----------

