Breaker double tapping

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dswearingen

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Is it allowed? Couldn't find it under switches (404), nor under circuit breakers used as (240). Don't normally do this, and home inspectors regularly flag it, but a friend electrician asked and I told him I would look it up. Can't say conclusively. Anyone? Thanks in advance.
 
To add to what Tom mentioned, if the breaker manufacturer lists the breaker this way then it's OK to land two wires on the breaker. These breakers are easily identifiable. Basically, if the breaker has a center screw, clamp-down plate where a wire can be inserted on either side of the screw it's approved for use with two wires. On the other hand if you use, say a Siemens breaker, where the wire is inserted into a small port on the load side of the breaker and the bottom of the screw is the sole means of clamping down on the wire then it's not approved for use with two wires in it.
 
Here's an example of a legal installation of two wires under one CB terminal. Sorry for the so-so quality I only had my point and shoot.

IMG_2082.JPG
 
Rob,
I don't see anything on the label that says the terminal is suitable for two conductors. It must be so marked to be used with two. It does show the permitted wire size, but does not specify how many. It may be on another part of the breaker, but I don't think so.
 
don_resqcapt19 said:
Rob,
I don't see anything on the label that says the terminal is suitable for two conductors. It must be so marked to be used with two. It does show the permitted wire size, but does not specify how many. It may be on another part of the breaker, but I don't think so.
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But it could still be part of the listing of the CB correct?
 
infinity said:
But it could still be part of the listing of the CB correct?
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I don't think that is good enough. The device has to be marked to show the terminals can be used with more than one conductor. The UL White Book information for "Electrical Equipment for Use in Ordinary Locations (AALZ) says :
Terminals ? Product terminals, including wire connectors and terminal screws, are acceptable for connection of only one conductor, unless there is marking or a wiring diagram indicating the number of conductors which may be connected.
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In the photo, I would expect to see a (2) in front of the wire sizes on the label if you are permitted to use two conductors on that breaker.
 
don_resqcapt19 said:
In the photo, I would expect to see a (2) in front of the wire sizes on the label if you are permitted to use two conductors on that breaker.
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Even Sq D QO CB's don't say (2) on the wire range. They do have a diagram on the side. This CB may also have one I don't know for sure.
 
infinity said:
Actually for commercial and industrial 480/277 volt panelboards GE products are very well made. IMO SQ D products for these applications are no better.
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Sorry but this old boy has bad taste for anything that says GE . Was in TV repair from late 60's to early 80's , no thanks simply don't trust GE anything. Seen plenty of there cheap panels. Simply no trust in them.
 
infinity said:
Even Sq D QO CB's don't say (2) on the wire range. They do have a diagram on the side. This CB may also have one I don't know for sure.
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I think would be ok on the side. I don't think the GE breakers are so marked. I didn't have a THED to look at close by, but I did have a TED with the same style of termination and there was no marking that said it was suitable for more than one conductor. I took a quick look at the GE Industrial website but didn't find anything, however I rarely find what I am looking for on their site...doesn't seem to be too user friendly to me.
 
don_resqcapt19 said:
I think would be ok on the side. I don't think the GE breakers are so marked. I didn't have a THED to look at close by, but I did have a TED with the same style of termination and there was no marking that said it was suitable for more than one conductor. I took a quick look at the GE Industrial website but didn't find anything, however I rarely find what I am looking for on their site...doesn't seem to be too user friendly to me.
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You may be right. I saw this CB at work today and remembered this thread so I snapped a photo. Looking at the U shaped clip it seems to be set up for either one or two conductors but unless it's marked on the side I don't see that it's actually listed for two conductors.

And you're correct about the GE site, it's downright horrible. If you take the CB # right from the photo and input it into their search engine you will come up with nothing.
 
The flat plate is not necessarily an indication of accepting two wires. Cutler Hammer CH styles breakers only have a round hole, but they are listed for two conductors per terminal in 15, 20, and 30A sizes (and maybe a 25A -- never seen one though). They are marked with a (2) on the side in front of the conductor size when between #14 and #10.
 
suemarkp said:
The flat plate is not necessarily an indication of accepting two wires. Cutler Hammer CH styles breakers only have a round hole, but they are listed for two conductors per terminal in 15, 20, and 30A sizes (and maybe a 25A -- never seen one though). They are marked with a (2) on the side in front of the conductor size when between #14 and #10.
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When you look at the photo it's likely that the two #10 conductors will remain tight under that plate for the next 100 years. Not saying that it's listed that way but from the looks of the design, the connection there shouldn't ever be a problem especially with two conductors of the same size. Now is it compliant, maybe not.
 
infinity said:
But it could still be part of the listing of the CB correct?
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Also, we can't see under the wire,
to see if there are TWO landing areas,
indicated perhaps by two grooves.

However,
from the top side,
there appears to be an extra WIDE landing,
far too wide for #12 or #10.
 
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infinity said:
When you look at the photo it's likely that the two #10 conductors will remain tight under that plate for the next 100 years. Not saying that it's listed that way but from the looks of the design, the connection there shouldn't ever be a problem especially with two conductors of the same size. Now is it compliant, maybe not.
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You know I've always thought that section implied that the terminal had to be labeled as two conductor but what does the code actually say?

"Terminals for more than one conductor and terminals
used to connect aluminum shall be so identified."

What does identified mean?

Identified (as applied to equipment). Recognizable as
suitable for the specific purpose, function, use, environment,
application, and so forth, where described in a particular
Code requirement.

Recognizable as suitable? Almost implies that if it's obvious (such as the picture's CB terminal is IMO) it's fine.
 
Twoskinsoneman said:
You know I've always thought that section implied that the terminal had to be labeled as two conductor but what does the code actually say?

"Terminals for more than one conductor and terminals
used to connect aluminum shall be so identified."

What does identified mean?

Identified (as applied to equipment). Recognizable as
suitable for the specific purpose, function, use, environment,
application, and so forth, where described in a particular
Code requirement.

Recognizable as suitable? Almost implies that if it's obvious (such as the picture's CB terminal is IMO) it's fine.
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While not a code rule there is a FPN that address this issue.
Identified ... FPN: Some examples of ways to determine suitability of equipment for a specific purpose, environment, or application include investigations by a qualified testing laboratory (listing and labeling), an inspection agency, or other organizations concerned with product evaluation.
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glene77is said:
Also, we can't see under the wire,
to see if there are TWO landing areas,
indicated perhaps by two grooves.

However,
from the top side,
there appears to be an extra WIDE landing,
far too wide for #12 or #10.
Click to expand...


Look at the identical CB below the one with the two conductors.
 
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