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Kevin Moore
05-27-2012, 05:54 PM
Anyone have a pic or info on these? I know some are made for it but have never seen a back stabbed breaker designed for it and i could find no pic on breaker showing 2 wires.Electrician says it is,not that that means anything!

Robert Meier
05-27-2012, 06:21 PM
Sq D type QO are one of the few CB's listed for one or two conductors under the single terminal. This is from Sq D:


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.

Look at page 7 for wire size combinations:

http://www.cuny.biz/PDFs/Circuit%20Protection/Square%20D/QO%20Circuit%20Breakers.pdf

Alton Darty
05-28-2012, 12:48 AM
Anyone have a pic or info on these? I know some are made for it but have never seen a back stabbed breaker designed for it and i could find no pic on breaker showing 2 wires.Electrician says it is,not that that means anything!

Try these

Jim Port
05-28-2012, 06:44 AM
That would not be back-stabbed.

Both the Square D QO and Homelines in 15, 20 and 30 amp are listed for two conductor of equal size and material.

Some Cutler-Hammer are also listed for two conductors.

Garry Blankenship
05-28-2012, 07:52 AM
I need a little help on what back stabbed means. I am familiar w/ inexpensive receptacles & switches having quick wire openings on the back that you can stab a wire end into. Not aware of any C/Bs w/ terminations like that. Home Inspection trainers put too much emphasis on the dreaded "double tapping" of circuit breakers. As kindly demonstrated here, there are breakers approved for more than one conductor and some lugs and other devices are also approved for dual conductors. Conductors are typically "tapped" or spliced many times on their path. To be legal a breaker must be U/L listed for two conductors, but in the grand scheme of electrical problems, it is a comparatively minor issue to have two conductors, ( of the same size ), in a C/B termination, ( 30 amps or less ).

Jim Port
05-28-2012, 08:07 AM
Back-stabbed would be like the quick wire terminals on a device where spring tension holds the conductor in place.

Back-wired devices have a clamping plate that holds the conductor and is much more reliable than the stab.

I have seen older Square D breakers that had quick wire terminals like the devices, but not for many years.

Alton Darty
05-28-2012, 08:15 AM
I need a little help on what back stabbed means. I am familiar w/ inexpensive receptacles & switches having quick wire openings on the back that you can stab a wire end into. Not aware of any C/Bs w/ terminations like that. Home Inspection trainers put too much emphasis on the dreaded "double tapping" of circuit breakers. As kindly demonstrated here, there are breakers approved for more than one conductor and some lugs and other devices are also approved for dual conductors. Conductors are typically "tapped" or spliced many times on their path. To be legal a breaker must be U/L listed for two conductors, but in the grand scheme of electrical problems, it is a comparatively minor issue to have two conductors, ( of the same size ), in a C/B termination, ( 30 amps or less ).

Jim, this was the only thing that I could think that the OP might be referring to.
Gary, with two wires of different gauges or even with two wires of the same gauge under a terminal that is only designed for one conductor I really would not call it a minor issue. Normally, when I see double taps I find plenty of other issues with the electrical of the structure.
If the terminal is designed for one wire adding another conductor is improper. The NEC says so, as do the manufacturers. The breaker, terminal, or lug must be marked as suitable, or the manufacturers labeling must say that the connection is suitable for more than one conductor, if not it is a violation.

H.G. Watson, Sr.
05-28-2012, 08:53 AM
Anyone have a pic or info on these? I know some are made for it but have never seen a back stabbed breaker designed for it and i could find no pic on breaker showing 2 wires.Electrician says it is,not that that means anything!

Please provide a picture of what you're concerned about.

Garry Blankenship
05-28-2012, 09:00 AM
Jim, this was the only thing that I could think that the OP might be referring to.
Gary, with two wires of different gauges or even with two wires of the same gauge under a terminal that is only designed for one conductor I really would not call it a minor issue. Normally, when I see double taps I find plenty of other issues with the electrical of the structure.
If the terminal is designed for one wire adding another conductor is improper. The NEC says so, as do the manufacturers. The breaker, terminal, or lug must be marked as suitable, or the manufacturers labeling must say that the connection is suitable for more than one conductor, if not it is a violation.

Copy that Alton. I would call it out, if the termination is not listed for two conductors. Also agree that one violation is a tip of more to follow. Hopefully you noticed that I qualified conductors of the same size and that to be legal they must be so listed. Not legal - - - yes. It is, however, just another splice and missleading to emphasize it as an egregious violation when there are so many problems that represent more potential danger. Most landing pad openings, ( ground & neutral bars ), are not "approved" for dual conductors, but OK for stranded conductors. So how dangerous is it when an electrician twists ground wires into a stranded conductor and terminates that in a lug opening ? There is illegal and there is dangerous; just sayin.

Jim Port
05-28-2012, 09:22 AM
The closest I have seen anything listed for a stranded conductor is a device for use with finely stranded conductors.

The bus terminals are listed for use with multiple grounding conductors, not their construction. Neutrals are limited to one per hole.

I would not consider two conductors twisted together the same as a stranded conductor.

Garry Blankenship
05-28-2012, 09:43 AM
A better web Maestro than I could probably find some conductor stranding standards, but the smallest number I have seen in a mfg. cable is seven strands. I know the finer the stranding, the more flexible the cable and on tough / tight raceway pulls it can make a difference. Some, ( most ? ), openings in landing bars will take a #6 ga. Donno how many # 14s ot 12s that might be, but I would not be alarmed by three to a half dozen ground wires twisted together and terminated in a single opening, ( like a stranded #6 ground rod wire ).

paul hardy
05-28-2012, 10:24 AM
Zinsco made a breaker that was similar to back stab you flipped a little lever than installed the conductor then flipped the lever back to secure the conductor dont think it would matter how many conductors you could put in because its zinsco and should be replaced.

Kevin Moore
05-28-2012, 02:58 PM
By back stabbed i would guess i mean quick wire as Jim said. Not sure what type of breaker it was as there was no info on it whatsoever and i could find nothing on it that would indicate it was ok for two wires in one slot as the electrician said. I just told my client that due to the other electrical issues we found i would have it evaluated/fixed. As others have said its an easy fix, i was just curious as i have never ran accross this before.Thanks for the responses.

Alton Darty
05-28-2012, 04:03 PM
Kevin, do you have any photos that you could share with us? The Zinscos that Paul referred to are the only ones that I have ever seen with any type of quick wire device.

Kevin Moore
05-28-2012, 07:55 PM
I'll see if i can find one on my phone and post it if i do.