Why do some breakers have two wire receiving slots?

[MrMark]

Is this to combine two circuits into one at the panel? Any concerns with this practice other than observing proper circuit loading?

Single pole breakers is the subject.

 

[Alchymist]

From what I understand if the breaker has provisions for two wires, it's ok to put two circuits on it, within max load ratings. If the breaker is not designed for two wires, it's a no-no. Square D QO breakers come to mind. Of course there is the ever present AHJ that may say no.

No different from a circuit with one wire going to a junction box and picking up two others.

 

[Torque1st]

Get yourself a book on basic electrical wiring at the library or Box store.

 

[ishiboo]

Is this to combine two circuits into one at the panel? Any concerns with this practice other than observing proper circuit loading?

Single pole breakers is the subject.

Yes, and not really from a technical standpoint... other than having too many wires in the panel. However most of the time, it's easy to feed everything you need in series using a single wire, and it's usually cleaner to do so.

On occasion it becomes convenient to run two into one breaker. Sometimes, you also may wish to combine to free up capacity.

 

[Zeke]

Get yourself a book on basic electrical wiring at the library or Box store.

Nice answer. I have a couple or wiring books and these breakers are not mentioned.

Try to be a little more helpful and a little less snide.

 

[MrMark]

Get yourself a book on basic electrical wiring at the library or Box store.

Haha. Nice one for a guy who uses the "triangle" for ohm's law. Is that really you in your avatar? I figured that or the guy in the basement that puts the lotion on the skin.

 

[ishiboo]

Nice answer. I have a couple or wiring books and these breakers are not mentioned.

Try to be a little more helpful and a little less snide.

I think it's easy to read into the question as a noob, MrMark has a good understanding of electrical practice, someone unfamiliar with his posts may not know.

The obvious answer is "a second wire", but in practice (especially with code) things become a lot more complex

 

[MrMark]

Yes, and not really from a technical standpoint... other than having too many wires in the panel. However most of the time, it's easy to feed everything you need in series using a single wire, and it's usually cleaner to do so.

On occasion it becomes convenient to run two into one breaker. Sometimes, you also may wish to combine to free up capacity.

I figured that, thanks. I have seen the wire nuts in a few panels and I imagine that was a case of either cutting wires too short or combining two blacks into one pigtail to a breaker to free up space.

It seems a rather untidy practice but may sometimes be the only reasonable way to free up breaker space it seems.

 

[Charles (in GA)]

The only breakers I've ever seen that have two wire attach points for a single pole breaker, are the Square D Homeline series. They have a flat plate with two humps in it and a screw between the humps and you can put two wires on them, they are designed for that. Never seen any other brand made like that.

Charles

 

[ishiboo]

The only breakers I've ever seen that have two wire attach points for a single pole breaker, are the Square D Homeline series. They have a flat plate with two humps in it and a screw between the humps and you can put two wires on them, they are designed for that. Never seen any other brand made like that.

Charles

QO and CH's BR are designed for two wires as well. I assumed it was common.

 

[Norcal]

In order to put 2 conductors in 1 breaker load terminal you need proof from the manufacturer that it is listed for that, SQ D QO & HOMOline are OK for that not sure about the BR, as will not use them since I despise them almost as much as Zinsco.

 

[Torque1st]

Haha. Nice one for a guy who uses the "triangle" for ohm's law. Is that really you in your avatar? I figured that or the guy in the basement that puts the lotion on the skin.

If you had ANY knowledge of basic household electricity you would not be asking such a question. And you would have known Ohm's Law and how to use it and not make dumb comments.

My avatar is a character from Beyond Thunderdome.

Mr Mark obviously IS a noob at electrical work.

 

[rockwithjason]

so what if he is a noob? that is what this area is for. people who are not pros come here and ask people who are pros. hell i have been doing this **** for 18 years and i still ask questions and learn things all the time, no shame in it for me.

 

[ForceFed70]

If you had ANY knowledge of basic household electricity you would not be asking such a question.

Mr Mark obviously IS a noob at electrical work.

Who peed in your cherios this morning?

Seriously, he is asking a question. He obviously doesnt know the answer which is why he is asking. This isnt an experts only forum or even an advanced forum.

I would argue that I have a basic understanding of household electricity and I personally dont know that answer to this one either.

Telling someone to go buy a book is just arrogant.

 

[LIVELY]

When your too stinking smart to ask ?????? then you are not much good at anything!!!

The smart man is not afraid to ask ??? so he can get the right answer-from most people .

I think it was a great ? thank you for the answers guys

 

[StaggeringGoat]

If you had ANY knowledge of basic household electricity you would not be asking such a question. And you would have known Ohm's Law and how to use it and not make dumb comments.

My avatar is a character from Beyond Thunderdome.

Mr Mark obviously IS a noob at electrical work.

I wish everybody was born an electrical genious the way you were.

This board is designed for people to ask questions they don't know the answers to, and for others who do know the answers to give a reply. If you can't follow that simple idea then you shouldn't be here.

Whether somebody is a "noob" or not is entirely irrelivant.

When your too stinking smart to ask ?????? then you are not much good at anything!!!

Amen.

 

[Neuswede]

Nice answer. I have a couple or wiring books and these breakers are not mentioned.

Try to be a little more helpful and a little less snide.

Agreed.

Most "books" available at the box stores are fairly general in nature, and I found none of these mentioned in any of mine.

Also, wire nuts in the main box are a code violation.

Lastly, if we are talking about associated, multi-conductor circuits; they need to be identified with wire ties; this is new in NEC2008; was not required in NEC2006.

DISCLAIMER:I am not an electrical genius, nor do I play one on the internet.

 

[Displaced Hokie]

Boo for being unhelpful! Yay to those that helped the OP!

 

[Charles (in GA)]

Also, wire nuts in the main box are a code violation.

I would be interested to see the code cite on this, as I've never seen or heard of this before.

Lastly, if we are talking about associated, multi-conductor circuits; they need to be identified with wire ties; this is new in NEC2008; was not required in NEC2005.

Fixed it for 'ya.

Charles

 

[Charles (in GA)]

From a Square D brochure I found on the Schneider web site............ The number in (?) before the wire size is the number of wires permitted in the terminal. Only standard QO 10 to 30 amp breakers allow for two wires on the termination......................

Terminations
The 10–30 A circuit breakers have pressure plate terminals suitable for single or two-wire terminations.
Copper or aluminum conductors may be used as outlined in Table 2. QO-GFI 15–30 A and QO-AFI
circuit breakers have pressure plate terminals suitable for single-wire terminations. These circuit
breakers are suitable for use with 60°C or 75°C conductors.
The QO 35–200 A and all QO-PL and QOT tandem circuit breakers have box-type lugs suitable for
single-wire terminations. These circuit breakers are suitable for use with 75°C conductors.
Special Application Circuit Breakers
There are several special application circuit breakers in the QO family:
• QO-HM and QOB-HM High-Magnetic Circuit Breakers
• QO-HID and QOB-HID Circuit Breakers
• QO and QOB Miniature Switches
• QOK and QOBK Key-Operated Circuit Breakers
• QO-GFI and QOB-GFI Qwik-Gard® Circuit Breakers
• QO-EPD and QOB-EPD Equipment Protection Devices
• QO-SWN and QOB-SWN Switch Neutral Circuit Breakers
• QOT Tandem Circuit Breakers
• QO-PL and QOB-PL Powerlink® Circuit Breakers
• QO-AFI and QOB-AFI Branch Feeder Arc-Fault Circuit Interrupters (AFCI)
• QO-CAFI, QOB-CAFI Combination Arc-Fault Circuit Interrupters (AFCI)
This following sections describe the special application circuit breakers and provides application
information for their use.
Table 2: Terminations
Circuit Breaker Types Rating Wire Size
QO, QOB, QO-VH, QOB-VH
10–30 A (1) 14–8 AWG (1.5–3.3 mm2) Al/Cu
(2) 14–10 AWG (1.5–2.6 mm2) Cu

35–70 A (1) 8–2 AWG (3.3–6.5 mm2) Al/Cu

80–125 A (1) 4–2/0 AWG (5.2–9.3 mm2) Al/Cu

QO, QOB, QO-VH 150–200 A (1) 4 AWG–300 kcmil (5.2–50 mm2) Al/Cu

QOB-VH 110–175 A (1) 4 AWG–300 kcmil (5.2–50 mm2) Al/Cu

QOT 15–20 A (1) 12–8 AWG (2.0–3.3 mm2) Al
(1) 14–8 AWG (1.6–3.3 mm2) Cu

QO-CAFI, QO-AFI, QO-GFI, QO-EPD,

QOB-CAFI, QOB-AFI, QOB-GFI, QOB-EPD 15–30 A (1) 12–8 AWG (2.0–3.3 mm2) Al (1) 14–8 AWG (1.6–3.3 mm2) Cu

QO-GFI, QO-EPD,

QOB-GFI, QOB-EPD 40–60 A (1) 12–4 AWG (2.0–4.1 mm2) Al
(1) 14–6 AWG (1.6–4.1 mm2) Cu

QO-PL 10–60 A (1) 12–2 AWG (2.0–6.5 mm2) Al

 

[Charles (in GA)]

THIS GE brochure offers no indication that their residential series breakers accommodate more than one wire per terminal, see p.14 (PDF file p. 15).

Charles

 

[Charles (in GA)]

THIS Eaton/C-H document shows that 15 and 20 amp CH breakers are approved for one or two wires, and for BR breakers (formerly Bryant) there is no indication that they are allowed to accept two wires. See Data Tables 1-2 and 1-3 and 1-10 and 1-11.

Charles

 

[Neuswede]

Also looked at the service panel requirements:

Article 110-3(b) of the NEC states that Listed or labeled equipment shall be used or installed in accordance with any instructions included in the listing or labeling. Just because a breaker fits in the panel does not mean that it is okay to install it in that panel.

If a particular breaker is labeled as meeting a certain "classification", then it complies with this specification. When UL tests a particular breaker, they do so as to meeting a certain classification; not a particular manufacturer's specification.

All service panels contain the typical legal-eze: Only use Type ** or Brand ** breakers or you void the manufacturer's warranty... blah, blah, bladdy, blah, blah.

Also on the wire nuts, read section 312.8...about as clear as mud. It addresses the use of "gutter-area" in service panels. My pre-purchase home inspection found these used within the service panel and was an immediate failure. We also found enough other issues that we gutted the wiring and installed all new service panel and new circuits before moving in.

While NEC is a good starting point, each state and even localities can have differing interpretation of what should or shouldn't be permitted.

Just an FYI.

 

[sdowney717]

http://activerain.com/blogsview/1441465/how-to-fix-double-tapping-at-circuit-breakers
http://www.nachi.org/forum/f19/double-lugged-breakers-28267/
I was flat out told NO to this by my electrical inspector.
Not sure why it came up when he did my inspection. I think it crossed my mind at the time you could do that.
But he threw cold water on the idea. Said just use a wire nut.
The above articles shows it ought to be ok if the breaker was made to do it.

 

[ishiboo]

http://activerain.com/blogsview/1441465/how-to-fix-double-tapping-at-circuit-breakers
http://www.nachi.org/forum/f19/double-lugged-breakers-28267/
I was flat out told NO to this by my electrical inspector.
Not sure why it came up when he did my inspection. I think it crossed my mind at the time you could do that.
But he threw cold water on the idea. Said just use a wire nut.
The above articles shows it ought to be ok if the breaker was made to do it.

Yup, just ignorance if you had a panel that supports it. I highly doubt any local code would override something like that, it's perfectly safe.

 

[rabidsquirrel]

Also on the wire nuts, read section 312.8...about as clear as mud..

It's actually very clear. As long as you have sufficient wire fill, you can splice in a panel enclosure. Think of it as a large junction box. Failing a home inspection on that is asinine. The more I hear about home inspectors, the more I think they are a waste of money.

 

[Charles (in GA)]

It's actually very clear. As long as you have sufficient wire fill, you can splice in a panel enclosure. Think of it as a large junction box. Failing a home inspection on that is asinine. The more I hear about home inspectors, the more I think they are a waste of money.

And adding a splice or two, or even several, is not going to come close to the fill limits they specify. Its not uncommon to have splices in panels when you replaced a smaller, older panel with a new, large one. The wires never reach to the breaker, so you end up splicing them, or running a new wire back to the first junction, which is time consuming. You need to get that panel in and working right away, so you splice in the panel.

Charles

 

[Zeke]

No wire nuts in the breaker panel around here. When doing a service change out, a box is often placed next to the panel where all such connections are made.

 

[Fred Ming]

Nice answer. I have a couple or wiring books and these breakers are not mentioned.

Try to be a little more helpful and a little less snide.

I gotta say, that's how it felt when I read his post. Soldier on . . .

 

[hh76]

to the original question, two wires if fine if the breaker is designed for it, but beware that an inspector may need to see proof, so have paperwork ready.

When it comes to failing a home inspection because of wire nuts in a LC, almost every older home I've ever worked on would fail if that were true. When doing a service swap, some do mount a gutter, or box to make connections, but usually it is if they know they will have to make up a lot of spices.

As far as "get a book" answers, I do think they have a place. I don't think we should encourage some people to pursue electrical work without doing some homework, esspecially when they ask questions that show that they have absolutely no idea what is going on. For this post, I think it is a great question, and I definately don't think it warrents that type of attitude. I imagine that there are a lot of electricians out there who are unaware of the rules.

 

[z28dad]

I dont guess I have ever seen one. When I read the post I was thinking about an af or gf.. Most of the stuff I have worked on is ch brand.

 

[54FordPanel]

I gotta say I've been impressed with MrMark's electrical knowledge in the past, so I'm learning something by him asking the question.

 

[Fred43]

Hey, I've been doing this for almost 50 years and there is always something to learn. Sometimes from those new to the trade as well as those that pass on their yeas of knowledge. Snobbery is fine for fun but not to poke fun at a serious question.

Yes QO Sq "D"'s are made for two wires. Westinghouse, Bryant, Cutler Hammer BR's are not designed for two except the breaker lug will accept two wires. Some inspectors will approve the practice if you twist the wires together and they are the sam AWG.

It is not illegal to splice wires in a panel if you do not use up more than 40% of the wireway.

 

[Fred43]

hh76,
Good points.
I used to make a lot of money going out to check on HOME INSPECTOR's claims of poor wiring and equipment that need to be replaced. About 75% of the claims were bogus. The home inspectors take a 10 hour course in the five major trades and consider themselves experts. I used to charge to write a report for the buyer or seller so they could take it to the passing. After the passing I might consider working in the home, if asked to, to defray thought of bias in the report.

 

[Milton Shaw]

Haven't seen it mentioned but don't GCFI breakers always have terminals for two wires, the black and the neutral. They also always have the pigtail for connecting to the neutral. Could this be what the original poster was asking about "terminals for two wires".

 

[DYNA BILL]

Get yourself a book on basic electrical wiring at the library or Box store.

If you had ANY knowledge of basic household electricity you would not be asking such a question. And you would have known Ohm's Law and how to use it and not make dumb comments.

My avatar is a character from Beyond Thunderdome.

Mr Mark obviously IS a noob at electrical work.

There are no stupid questions, but there are stupid answers.
You, sir, gave stupid answers.

 

[Torque1st]

There are no stupid questions, but there are stupid answers.
You, sir, gave stupid answers.

Jesus, I had many old timers here compliment me on my answer to this OLD thread that some newbie with one post opened back up. My answer was appropriate for the knowledge level of the OP.

That idiotic 'truism' you quoted is one of the dumbest things I have ever heard. A palliative for the ignorant masses. One would have to be rock stupid to go around quoting it...

 

[DYNA BILL]

Ironically, your signature says a lot about you.

 

[Torque1st]

Thank you!

 

[rburke65]

Ditto....not very helpful.