# Tricks for quickly figuring out circuit colors



## AmishCountrySparky (Mar 25, 2016)

I was just curious if some of you have a quick way to figure out your circuit colors for pulling wire. ( say your pulling 27, 29, 31, 12, and 18 in a pipe) A older electrician had some system he used that he showed me a few years ago, but I forget it. I think it had something to do with being a multiple of three or something like that. I know there has to be a better way than starting at one or two and just using your fingers. Haha. Any tricks or quick methods would be appreciated


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## MXer774 (Sep 1, 2014)

I have a hand written note that I took a picture of with my phone. Circuits 1-42 with A,B,C separating the numerical digits.

If I were pulling wire for an extended period of time, I would rip a piece of cardboard off a box and write out the numbers and phases so I wouldn't be pulling out my phone all the time. I'd keep it in my back pocket for quick reference. 

I have been taught what you were referring to but I can't remember either. I found that what I explained above worked best for me.


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## HackWork (Oct 2, 2009)

Wow, it's been so long that I completely forgot what to do lol...'

Here is a post I made explaining one way to do it a long time ago: http://www.electriciantalk.com/f2/a...heat-sheets-circuit-numbers-17257/#post302920


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## splatz (May 23, 2015)

...wait....


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## HackWork (Oct 2, 2009)

The easiest way to remember is that the circuits are grouped together by 6 and then repeat. 

1 2 A
3 4 B
5 6 C

So just divided by 6 and the remainder will be the phase that you are on.


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## AmishCountrySparky (Mar 25, 2016)

Thats what I was looking for Hack. Thanks!


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## kg7879 (Feb 3, 2014)

C phase is divisible by 6 like others have stated and the B phase is divisible by 3 on the odd side.

or use Hacks method. I have never heard of that but that is a good way to figure it out.


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## Cow (Jan 16, 2008)

I use the divide by six and the remainder is the phase method, also.


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## RunningSparky (Feb 9, 2013)

+1
On the divide by 6 method, still tried and true for me.


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## millerman2008 (Jan 18, 2018)

6 is all you need to remember. Never heard of 3 before, even though 3 would make sense since it's a 3 phase panel, but 6 is much easier. Wait till you have to pull in circuit 87 into 2 42 breaker panels nippled together, with a third smaller panel nippled to the last one. Normally you name each panel separately, but they do stuff like that in Florida in commercial applications. I've seen it at Disney before.


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## millerman2008 (Jan 18, 2018)

millerman2008 said:


> 6 is all you need to remember. Never heard of 3 before, even though 3 would make sense since it's a 3 phase panel, but 6 is much easier. Wait till you have to pull in circuit 87 into 2 42 breaker panels nippled together, with a third smaller panel nippled to the last one. Normally you name each panel separately, but they do stuff like that in Florida in commercial applications. I've seen it at Disney before.



Forgot to mention, 1 or 2 remainder is A phase. 3 or 4 remainder is B phase, and a remainder of 5 or zero is C phase. It never fails for all 3 phase panels.


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## Dizzykidd (Aug 3, 2016)

Use a tape measure. Every ft mark is blue the use the inch mark after to figure out the others. That way you only have to memorize one through 12. For instance if your pulling circuit 14, on a tape it'll read as 1ft 2 in. 2 is black.


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## splatz (May 23, 2015)

Maybe a cheat sheet is better...


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## Arrow3030 (Mar 12, 2014)

I like equations. Here's one that works.

1/2x - 3y = z

x = your circuit number. It's even (or odd + 1)

*y = the number of 6's added together using base 6 to equal one less than x.

z = 1, 2 or 3 where one is A phase, two is B phase and three is C phase.

*optional for y*
y = a whole number that results in z being equal to 1,2 or 3. For a 42 space panel y is 0 through 6 fyi.

Example: what phase is circuit 38 on? 

1/2(38) - 3(6) = 1 

38 is on A phase.

Here's how to count in base 6:
0, 1, 2, 3, 4, 5, 10, 11, 12 ,13, 14, 15, 20....55, 100, 101, 102......


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## HackWork (Oct 2, 2009)

splatz said:


> Maybe a cheat sheet is better...


I'm still waiting for your other post :vs_mad:


As for the cheat sheet, that works when doing a bunch and you have the cheat sheet out. But it's really just as fast to do the math.

If you picture the top 6 spaces of a panel in your head it goes quick. 27... remainder of 3... B phase.


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## Bird dog (Oct 27, 2015)

splatz said:


> Maybe a cheat sheet is better...


I made up a cheat sheet similar to @*splatz* 's except it was 1-42 with excel. I printed it out and laminated it in a size that fit in my wallet. I think my version had even numbers on one side & odd on the other. You'll have to play with it to get what works for you.


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## MechanicalDVR (Dec 29, 2007)

HackWork said:


> The easiest way to remember is that the circuits are grouped together by 6 and then repeat.
> 
> 1 2 A
> 3 4 B
> ...


Wow that was a golden oldie from years gone by.


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## Bird dog (Oct 27, 2015)

Or you can just count on three of your fingers 1-3-5 etc or 2-4-6 etc. 19 & 20 are black to cut your counting.


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## glen1971 (Oct 10, 2012)

HackWork said:


> The easiest way to remember is that the circuits are grouped together by 6 and then repeat.
> 
> 1 2 A
> 3 4 B
> ...


 
That's how I was shown and it is easy to remember..

Also divide by 4 to find the "B" phase in a single phase panel... Same rule for the remainder...


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## ralpha494 (Oct 29, 2008)

I have the following on a cheat sheet for the code book for apprentices:

*Determining "C" Phase

*In a three phase panel, whether numbered sequentially 1 through 21 down the left side, or odd numbers 1 to 41 down the left side, "C" phase will always be divisible by 6. (Any even number whose digits add up to a number divisible by 3.) Examples:
24: 2+4 = 6; 24/6=4 78: 7+8=15; 78/6=13. 114: 1+1+4=6; 114/6=19.


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## 220/221 (Sep 25, 2007)

The first half of the number sequences are probably stuck in our brains and can be counted out quickly.


After that, if you can divide it by six, it's C phase, along with the one before it.

After that, count forward or back.


Or, there HAS to be an app for it somewhere.


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## Arrow3030 (Mar 12, 2014)

If it's an odd circuit # and a multiple of 3 it's on B. If It's an even circuit # and divisible by 3 it's on C.

Numbers divisible by three always have a digital root of 3, 6 or 9 

Any number divisible by 6 is divisible by 3. Only even numbers are divisible by 6 because 6 is even and not prime. Dividing by 6 isn't that hard but it's twice as hard as dividing by 3.

Dividing even numbers by 6 is cutting yourself short. You're missing out on easy odd number B phase. You're also most likely doing division by memorizing times tables and missing out on arithmetic.

If you divide by six and add the remainder rule that's fine.


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## HackWork (Oct 2, 2009)

I don't know why you people are complicating this.

Divide by 6 and the remainder is your answer. Can it get any simpler?


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## Arrow3030 (Mar 12, 2014)

I like numbers more than you. I imagine others do too.

Again, there's nothing wrong with your method hax.


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## HackWork (Oct 2, 2009)

Arrow3030 said:


> I like numbers more than you. I imagine others do too.


I don't know what liking numbers means. I am still curious why you would purposely complicated something for absolutely no reason? 

It's like routing a cable an extra 100' out of the way just because you like wire.


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## Arrow3030 (Mar 12, 2014)

I'll post in non trade topics to continue.


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## splatz (May 23, 2015)

HackWork said:


> I don't know why you people are complicating this.
> 
> Divide by 6 and the remainder is your answer. Can it get any simpler?





Arrow3030 said:


> I like numbers more than you. I imagine others do too.
> 
> Again, there's nothing wrong with your method hax.


Hacks answer is really the simplest way to calculate this, there is little room for improvement on looking at the remainder and thinking about the first rows. 

A cheatsheet is good if you can make one, if you're going to be pulling a lot of wire, just slap it on the wall and save yourself the trouble of dividing by six all day. Less error prone. 

But, I like numbers, formulas, too, don't hate on the geekery people, not saying you should do it this way in the field  
 @Arrow3030 - here is a formula that works in a google spreadsheet 

where A1 contains the circuit number, this formula will give you the phase: 
=switch(mod(quotient(A1-1,2),3)+1,1,"A",2,"B",3,"C")

You take the circuit number minus one
divide that by two, discard the remainder - that's the quotient 
divide the quotient by three, the remainder (MOD) is the phase 
the switch part just converts 1 to A, 2 to B, 3 to C


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## mikedl361 (Dec 24, 2016)

splatz said:


> Maybe a cheat sheet is better...


 Thanks for the cheat sheet Splatz. It'll come handy.


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## The_Modifier (Oct 24, 2009)

Great suggestions!

If you're into python coding, *HERE* is my github for a 3 phase colour coding calculator.

I haven't been at it very long so I don't have a looping function- been a bit busy lately.

Feel free to contribute if you wish.:vs_cool:


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