Acceptable Method to Wire Outlet

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R Schick

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I am promoting looping (a stripped portion of) the neutral over the screw on the outlet then using a wire nut to connect to the wire for the next downstream outlet. The only acknowledgement in the NEC seems to be a note to 300.13 in the handbook. I am getting pushback from a colleague that this method is not noted in Exhibit 110.3 and therefore unacceptable.

Is this method clearly noted anywhere?
 
The exhibits aren't "code". They are the creator of the Handbooks notes, helps, and interpretation of the code.

Although they may be true, they are not enforceable.
 
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R Schick said:
I am promoting looping (a stripped portion of) the neutral over the screw on the outlet then using a wire nut to connect to the wire for the next downstream outlet. The only acknowledgement in the NEC seems to be a note to 300.13 in the handbook. I am getting pushback from a colleague that this method is not noted in Exhibit 110.3 and therefore unacceptable.

Is this method clearly noted anywhere?
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Is this a MWBC? Is that why you're doing this? That would be legal with a MWBC, but for anyother receptacle, it would be a waste of time rather than putting both wires on the receptacle.
 
This makes no sense to me.

First, what is the problem with feedeing through the recpetacle? :confused:

Second, if you are going to make a splice anyway why not just make up a pigtail? :confused:
 
While I can see some benefit to taking the receptacle components out of the circuit, IMHO a far better approach would be to use a pigtail.

Stripping a wire in the middle is considerably slower than stripping at the end, and if you screw up and nick the wire you have no recourse; if you strip at the end and screw up, you lose 1/2" of wire, but that usually isn't a problem.

Also worth considering are spec grade receptacles with pressure plates. These allow you to place two wires under a single pressure plate, and at least with stranded wires make quite good splices.

-Jon
 
Great additional thoughts.

The pigtail splice is a very reasonable path but does not answer the question as to acceptance of the loop-through by the NEC.

Removing of the break-off tab also reduces the number of series connects to loads. The loop-through results in one connection instead of two needed to feed through the break-off tab.

I do agree that the spec outlets provide a highly reliable feed through but again, two connections instead of one.
 
R Schick said:
I am promoting looping (a stripped portion of) the neutral over the screw on the outlet then using a wire nut to connect to the wire for the next downstream outlet. The only acknowledgement in the NEC seems to be a note to 300.13 in the handbook. I am getting pushback from a colleague that this method is not noted in Exhibit 110.3 and therefore unacceptable.

Is this method clearly noted anywhere?
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I say no. 110.3(B)

"Termination: Quickwire Push-In & Side"
http://www.leviton.com/OA_HTML/ibeCCtpItmDspRte.jsp?item=233713&section=24616

Click on http://www.leviton.com/OA_HTML/ibcG...=e1zgvSrhVF9KYodIcPxH0A&label=IBE&appName=IBE
 
I do not believe that there is any specific prohibition against stripping a wire mid span and looping it around a screw terminal. I'd be concerned that this installation technique has probably not been _evaluated_ for safety, and that there may be unknown failure modes caused by such an installation.

For example, the screw terminal as it is normally used would only have a single span of wire leaving the terminal, from one specific side only, since your loops are supposed to wrap around the screw in one direction. Using the 'mid-span loop' approach, you now have _two_ spans of wiring leaving the terminal, one of which leaves the terminal from the 'wrong' side. When pushing the receptacle into the box, these wires will put stress on the screw. There is potentially more mechanical force acting to break the connection. While I don't expect a problem, this is one of those things that might not have been evaluated for safety by UL or another lab.

The pictures that you post provide a strong argument for not passing the circuit through the receptacle, but still don't make the argument that the 'mid-span loop' will provide any benefit over pigtailing. Pigtailing does not pass the circuit through the receptacle, and just uses a single wire-nut, with 3 wires rather than 2.

-Jon
 
Mike: the receptacle is not providing any more than incidental conductivity to downstream outlets. If the screw on the receptacle becomes loose, the downstream loads are unaffected.

Jon: Your comments bring me to full agreement that a pigtail the solution and not loop-through.
 
R Schick said:
Mike: the receptacle is not providing any more than incidental conductivity to downstream outlets. If the screw on the receptacle becomes loose, the downstream loads are unaffected.

Jon: Your comments bring me to full agreement that a pigtail the solution and not loop-through.
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I'd agree with you if this was a real problem. There are a gazillion receptacles right now used as feed thru. Properly installed they are not a hazard.

I would bet, based on my own experience, that looping a conductor as you are promoting will actually make it harder to get a nice tight connection which will increase the likelyhood of the failure you are concerned with.
 
winnie said:
The pictures that you post provide a strong argument for not passing the circuit through the receptacle,
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No they don't. I bet the white receptacle was a victim of loose prongs when the plug was inserted. The second one could be any variation of a loose connection. These pictures proove nothing.
 
:confused:

I assume you are terminating copper conductors, no?
R Schick said:
I am getting pushback from a colleague that this method is not noted in Exhibit 110.3 and therefore unacceptable.
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Tell your colleague the "incorrect" terminations are shown in Exhibit 110.4 for aluminum wire and that the NEC is silent when the clockwise wrap is ~3/4 of the way around the screw as to whether the conductor ends under the terminal screw, after the terminal screw within X fractions of an inch, or ends after a length of additional insulated conductor.
2008 NEC Handbook

Exhibit 110.3 Correct method of terminating aluminum wire at wire-binding screw terminals of receptacles and snap switches.
Click to expand...
 
winnie said:
I do not believe that there is any specific prohibition against stripping a wire mid span and looping it around a screw terminal. I'd be concerned that this installation technique has probably not been _evaluated_ for safety, and that there may be unknown failure modes caused by such an installation.

For example, the screw terminal as it is normally used would only have a single span of wire leaving the terminal, from one specific side only, since your loops are supposed to wrap around the screw in one direction. Using the 'mid-span loop' approach, you now have _two_ spans of wiring leaving the terminal, one of which leaves the terminal from the 'wrong' side. When pushing the receptacle into the box, these wires will put stress on the screw. There is potentially more mechanical force acting to break the connection. While I don't expect a problem, this is one of those things that might not have been evaluated for safety by UL or another lab.

The pictures that you post provide a strong argument for not passing the circuit through the receptacle, but still don't make the argument that the 'mid-span loop' will provide any benefit over pigtailing. Pigtailing does not pass the circuit through the receptacle, and just uses a single wire-nut, with 3 wires rather than 2.

-Jon
Click to expand...


when we run a raceway, we just loop the wires in each box, and we do a mid span strip and loop the wire around the screw with out any cutting of the wire, this way the conductor just goes on to the next receptacle, we have never had a problem with this, and it is very common around here and was in Florida when I worked down there?

I see the OP is doing the same thing but making a code legal connection after the receptacle with a wire nut, I can not see how this would be a violation, just kind of an un-needed splice?
 
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