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Default 12/3 connected to 12/2 and 14/2

Greetings,

I would like to confirm that, according to the NEC, there is no reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).

Thank you for your time and energy,
William

  #2   Report Post  
Noozer
 
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" wrote in message
oups.com...
Greetings,

I would like to confirm that, according to the NEC, there is no reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).


Definately WRONG.

You cannot use 14 anything on a 20 amp breaker in any case.


  #3   Report Post  
 
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Dear Noozer,

Thank you for taking the time to answer but please first take the time
to read the post.

Thanks,
William

  #4   Report Post  
BobK207
 
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William-

Noozer did his best to answer your question.

Personally I was not able to understand it clearly enough to answer
it.

So unless you are willing to restate your original question more
clearly I sincerely doubt you will get a better answer.


:"I would like to confirm that, according to the NEC, there is no
reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).

So does this mean you'

running 12/3 from a 15 amp breaker
& also running 12/3 from a different 20 amp breaker

or have you created a shared neutral situation?

???

and then ~30ft away "branch" (branch what or which; each original
circuit ?)

into two two circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on
12/2)


is each original circuit be branched or just one of them?
do you intend to install the proper sized breakers to protect the 14/2?

bottom is 12/2 ok on 20 amp breaker, 14/2 is only ok when protected by
a 15 amp breaker

fyi when you're asking for free advice try not to **** of the guys with
the answers.

why the mixed breaker & wire size?

Just run it all in 12/3 & simplify your life.

cheers
Bob

  #5   Report Post  
RBM
 
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You absolutely cannot do that. Any person working in your panel would have
no way to know that the 12 awg had been reduced somewhere downstream and in
doing a service upgrade for example would install the wire to a 20 amp
breaker
" wrote in message
oups.com...
Greetings,

I would like to confirm that, according to the NEC, there is no reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).

Thank you for your time and energy,
William





  #6   Report Post  
SQLit
 
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" wrote in message
oups.com...
Greetings,

I would like to confirm that, according to the NEC, there is no reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).

Thank you for your time and energy,
William


I know of no code section that prohibits you from reducing the size of a
breaker on a given conductor.

As others said in the future there is a greater chance of someone installing
a oversized breaker for the smaller wiring. I would not do what your
suggesting.


  #7   Report Post  
toller
 
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You absolutely cannot do that. Any person working in your panel would have
no way to know that the 12 awg had been reduced somewhere downstream and
in doing a service upgrade for example would install the wire to a 20 amp
breaker


Actually, code specifically allows it. 210.3 "where conductors of higher
ampacity are used for any reason, the ampere rating or setting of the
specified overcurrent device shall determine the circuit rating".
This is frequently done where there is a long run from the breaker box to
the first outlet and there might be a voltage drop problem.

But unless you have a good reason to do it, it probably is best to be
consistent.


  #8   Report Post  
Rick
 
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"toller" wrote in message
...


You absolutely cannot do that. Any person working in your panel

would have
no way to know that the 12 awg had been reduced somewhere

downstream and
in doing a service upgrade for example would install the wire to a

20 amp
breaker


Actually, code specifically allows it. 210.3 "where conductors of

higher
ampacity are used for any reason, the ampere rating or setting of

the
specified overcurrent device shall determine the circuit rating".
This is frequently done where there is a long run from the breaker

box to
the first outlet and there might be a voltage drop problem.

But unless you have a good reason to do it, it probably is best to

be
consistent.



Agree...


  #9   Report Post  
 
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I would say that could be done, a bit confusing though. No real cost
savings in it either.

One thing that would be a problem with it though is if you used arc
faults to protect run in bedroom areas (gfci maybe too?) Their
neutrals go into the breaker and then to the busbar. No way of sharing
it.

  #10   Report Post  
 
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Greetings,

I have attempted to add clarity with the description below:

In the breaker box I have two single pole breakers.
One breaker is 15 amps.
One breaker is 20 amps.
The 15 amp is on pole A.
The 20 amp is on pole B.
There is a 30 ft piece of 12-3 attached to these breakers. (*creating
shared neutral situation)
The 15 amp is attached to the red wire.
The 20 amp is attached to the black wire.
At the other end of the 12-3 there is a utility box.
In this utility box the red and white wires have been attached to a
piece of 14-2.
In this utility box the black and white wires have been attached to a
piece of 12-2.
Is this a code violation?

Thank you very much,
William

Some responses to specific questions asked as follows:
Q: why the mixed breaker & wire size?
A: to reduce voltage drop to 5%. The portion of the run already in
14-2 is buried UF and would be a REAL pain to change.

Q: Any person working in your panel would have
no way to know that the 12 awg had been reduced somewhere downstream
A: They would suspect/know because it was attached to a 15 amp breaker



  #11   Report Post  
 
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Greetings,

I am not using AFCI or GFCI circuit breakers in either case.

Thank you,
William

PS: The cost savings come from using wire which is already run instead
of having to run new wire in difficult places.

  #14   Report Post  
 
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Based on what I hear I am going with it (unless I hear different from
someone who can site what code I am violating.)

The 20A load is for a bathroom / laundry room and is required to be 20A
by code (or else I would have to run another 20A circuit). The 20A
breaker is a standard sized breaker the 15A breaker is a mini-breaker
so I am not sure I could even purchase a tie bar if I wanted to.

Thank you all very much.

  #15   Report Post  
 
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Doesn't the NEC specify that a single, dedicated 20A circuit is
required for the washer/dryer receptacle? Or you already have that in
place and are running another 20A circuit for the bath portion?



  #16   Report Post  
 
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There are 5 circuits in the bathroom / laundry room (same room):
a) double pole 30 amp for the drier
b) 20 amp dedicated recepticle for washer/drier
c) 20 amp (other recepticles)
d) 20 amp heater
e) 15 amp lighting

  #17   Report Post  
toller
 
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" wrote in message
ups.com...
There are 5 circuits in the bathroom / laundry room (same room):
a) double pole 30 amp for the drier
b) 20 amp dedicated recepticle for washer/drier
c) 20 amp (other recepticles)
d) 20 amp heater
e) 15 amp lighting

And "C" is GFCI, right?


  #18   Report Post  
 
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C) is a GFCI receptacle on a NON GFCI breaker. Other receptacles on
same circuit are on the feed-through.

  #19   Report Post  
toller
 
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" wrote in message
oups.com...
C) is a GFCI receptacle on a NON GFCI breaker. Other receptacles on
same circuit are on the feed-through.

Thats all you need.


  #20   Report Post  
RBM
 
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Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire
size downstream is!!
"toller" wrote in message
...


You absolutely cannot do that. Any person working in your panel would
have no way to know that the 12 awg had been reduced somewhere downstream
and in doing a service upgrade for example would install the wire to a 20
amp breaker


Actually, code specifically allows it. 210.3 "where conductors of higher
ampacity are used for any reason, the ampere rating or setting of the
specified overcurrent device shall determine the circuit rating".
This is frequently done where there is a long run from the breaker box to
the first outlet and there might be a voltage drop problem.

But unless you have a good reason to do it, it probably is best to be
consistent.





  #21   Report Post  
 
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Dear RMB,

I am reducing the wire size downstream from 12 to 14 AWG on the 15 amp
breaker for the portion of the circuit without a shared neutral (see
full description previously posted). Based on what others say there is
no code issue here. Your argument that later no one will know not to
put a 20 amp breaker in in the future is false. They will know because
there is currently a 15 amp breaker installed so they need to find out
why before switching to a 20 amp breaker. You just can't go replacing
15 amp breakers with 20 amp breakers or 20 amp with 30 amp based on the
wire size entering the main panel. Unless you can provide some other
argument for your statement other than the debunked argument above I am
going to proceed as planned.

Thanks,
William

  #22   Report Post  
Bob Vaughan
 
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In article ,
Chris Lewis wrote:
According to :

I would like to confirm that, according to the NEC, there is no reason
why you cannot use 12/3 connected to 15 and 20 amp breakers (one on
pole A the other on pole B) and then (say 30 feet away) branch into two
circuits (a 15 amp circuit on 14/2 and a 20 amp circuit on 12/2).


[Your other posting made it clear that the 14/2 is on the 15A side, and
the 12/2 on the 20A side, and the common neutral is 12ga as it needs
to be.]

AFAIK, according to NEC rules this isn't illegal.

In CEC rules, the 12/3 in a box/shared neutral means that the breakers
must be tied. You can't get a 15A/20A pair, tied or otherwise. You
can tiebar singles, but that's frowned upon.

However, why bother? You're saving a few pennies at the expense
of possible future confusion, and some risk (from untied breakers).
By the time you factor in overshoot in having to buy two kinds of
wire versus one, and a dual 20A versus singleton 15A and 20A breakers,
chances are your approach costs you _more_.


His other posting also indicated that the 14/2 was buried UF, already in
place, and a PITA to change out.

As I see it, he has several options.

1. use the existing wiring as is, with existing breakers, and no handle ties
(legal under current NEC??, but not legal under CEC).

2. replace the single 20A breaker with a dual 20A breaker to match the
dual 15A in the next slot, and tie the adjacent 15 and 20 together.
(this will leave the extra 20 unused for future use)
unsure about availability of handle ties, as breaker type is
unspecified.

3. run a piece of 12/2 (or 14/2) from the panel to the utility box, and
move the 15A circuit off the 12/3, thus avoiding the shared neutral.
You may want to move the entire circuit into a new utility box.

4. replace the buried 14/2 UF with 12/2 UF, and the breaker with a 20A,
using the existing 12/3 w/shared neutral configuration.

5. options 3 and 4 combined.



I'd personally use a dual-tied 20A breaker (even if, strictly speaking,
you don't have to), and 12ga throughout.





--
-- Welcome My Son, Welcome To The Machine --
Bob Vaughan | techie @ tantivy.net |
| P.O. Box 19792, Stanford, Ca 94309 |
-- I am Me, I am only Me, And no one else is Me, What could be simpler? --
  #23   Report Post  
Bob Vaughan
 
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In article ,
Bob Vaughan wrote:

3. run a piece of 12/2 (or 14/2) from the panel to the utility box, and
move the 15A circuit off the 12/3, thus avoiding the shared neutral.
You may want to move the entire circuit into a new utility box.

4. replace the buried 14/2 UF with 12/2 UF, and the breaker with a 20A,
using the existing 12/3 w/shared neutral configuration.

5. options 3 and 4 combined.



I should have said:

5. options 3 and 4 combined, without the shared neutral.


--
-- Welcome My Son, Welcome To The Machine --
Bob Vaughan | techie @ tantivy.net |
| P.O. Box 19792, Stanford, Ca 94309 |
-- I am Me, I am only Me, And no one else is Me, What could be simpler? --
  #24   Report Post  
RBM
 
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William I don't have a code book handy, but I can assure you that your
assumption is incorrect. Reducing wire size downstream in the manner you
describe is illegal. Hopefully someone like Horne will pick this up and
direct you to the proper code section
" wrote in message
oups.com...
Dear RMB,

I am reducing the wire size downstream from 12 to 14 AWG on the 15 amp
breaker for the portion of the circuit without a shared neutral (see
full description previously posted). Based on what others say there is
no code issue here. Your argument that later no one will know not to
put a 20 amp breaker in in the future is false. They will know because
there is currently a 15 amp breaker installed so they need to find out
why before switching to a 20 amp breaker. You just can't go replacing
15 amp breakers with 20 amp breakers or 20 amp with 30 amp based on the
wire size entering the main panel. Unless you can provide some other
argument for your statement other than the debunked argument above I am
going to proceed as planned.

Thanks,
William



  #25   Report Post  
toller
 
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Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire
size downstream is!!


And your code reference is.............?!
It is not only acceptable, but is done all the time. Anyone who would
increase a breaker size without checking the circuit out should not be doing
any electrical work.




  #26   Report Post  
DL
 
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" wrote in message
ups.com...
Based on what I hear I am going with it (unless I hear different from
someone who can site what code I am violating.)

The 20A load is for a bathroom / laundry room and is required to be 20A
by code (or else I would have to run another 20A circuit). The 20A
breaker is a standard sized breaker the 15A breaker is a mini-breaker
so I am not sure I could even purchase a tie bar if I wanted to.

Thank you all very much.


You could also mark the breaker and note in the breaker box that the circuit
is wired in part with 14/2 so no breaker larger than 15amps should be used.
Won't prevent someone from adding a larger breaker that's determined, but it
should stop most people. Hopefully the load required from the outlet(s) at
the end of the 14/2 branch will be less than 15 amps in total. You can't
always save people from themselves. It is entirely possible for someone to
put a larger than 20 amp breaker on the circuits wired with 12/2-3.

David


  #27   Report Post  
RBM
 
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With what mystical power is one to determine that somewhere downstream the
wire size has been reduced
"toller" wrote in message
news


Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire
size downstream is!!


And your code reference is.............?!
It is not only acceptable, but is done all the time. Anyone who would
increase a breaker size without checking the circuit out should not be
doing any electrical work.



  #28   Report Post  
Doug Miller
 
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In article , "RBM" rbm2(remove wrote:
William I don't have a code book handy, but I can assure you that your
assumption is incorrect. Reducing wire size downstream in the manner you
describe is illegal. Hopefully someone like Horne will pick this up and
direct you to the proper code section


Since you're so confident that it's a violation, perhaps you'd be good enough
to cite the article of the Code which prohibits it?

Remember, he has *twelve* gauge wire coming off of a *fifteen* amp breaker
(for which 14ga would be sufficient), and he's reducing it later to 14ga.

That's *not* a problem.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?
  #29   Report Post  
Doug Miller
 
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In article , "RBM" rbm2(remove wrote:
With what mystical power is one to determine that somewhere downstream the
wire size has been reduced


Trace the cable. I'd certainly be inclined to do a bit of checking, if I saw a
12ga wire coming off a 15A breaker.


"toller" wrote in message
news


Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire
size downstream is!!


And your code reference is.............?!
It is not only acceptable, but is done all the time. Anyone who would
increase a breaker size without checking the circuit out should not be
doing any electrical work.




--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?
  #30   Report Post  
 
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Greetings,

Although I cannot quite explain it, I know that everyone loves photos.
I have included them at the URL below.

Thank you all very much again,
William

URLS:
http://tinyurl.com/awu4o

or
http://www.universityofsavanna.com/f...ical%20Photos/



  #31   Report Post  
Philip Lewis
 
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" writes:
They will know because there is currently a 15 amp breaker installed
so they need to find out why before switching to a 20 amp breaker.

or, you could be nice, and provide a written explanation stored
someplace close to the box. (at least tell them where to look ---
"see junction box above north wall in room blah")

--
be safe.
flip
Ich habe keine Ahnung was das bedeutet, oder vielleicht doch?
Remove origin of the word spam from address to reply (leave "+")


  #32   Report Post  
Doug Miller
 
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In article . com,
says...
Greetings,

Although I cannot quite explain it, I know that everyone loves photos.
I have included them at the URL below.

Thank you all very much again,
William

URLS:
http://tinyurl.com/awu4o

Lotsa wires in that box... Have you done a capacity calculation?

Mininum size of the box is
2.25 cubic inches per 12ga conductor, plus
2.25 cubic inches for the equipment grounds, plus
2.00 cubic inches per 14ga conductor

  #33   Report Post  
 
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Greetings,

I have added a box size calculation spreadsheet at bottom.
http://tinyurl.com/awu4o

Hope this helps,
William

  #34   Report Post  
 
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Thank you very much for your input Bob. I went with option One (see
other posts) because it was easy and code compliant.

Also, I actually like the shared neutral when possible. Less holes to
drill / wires to run / voltage drop / fewer or smaller boxes to install
/ neutral bar holes used* / grounds to come lose / etc etc. These are
general benefits, not specific benefits of this job.

*Believe it or not I had one subpanel with all mini-breakers that ran
out of neutrals bar holes but still had slots for breakers. Inspectors
here will only allow one neutral under a terminal on the neutral bar
but grounds can be twisted.

  #36   Report Post  
John Smith
 
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RBM wrote:

Putting a 12awg on a 15amp breaker is not the problem. Reducing the wire
size downstream is!!
"toller" wrote in message
...

Every 15 amp breaker in my house (Built in 1986) has a 12 gauge feeder
to the first recepticle/box.
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