Electrical: when are loops at screw terminals allowed?

Hi,
I'm interested in when it is allowed (NEC) and advisable to make a connection in an electrical box of a wire to a screw terminal by looping the wire around and then using the free end for another connection. Here's what I think I know:
1) It is NOT allowed to do this with the hot or neutral conductors and the screw terminals on a device. Use pigtails.
2) It is allowed to do this with the EGC and the grounding screw of a metal box or strap. This is a good idea, because it makes a neater, tighter installation.
So I think this only leaves the case of the EGC and the ground screw on a device. Is looping allowed here? Is it a good idea?
Thanks, Wayne
P.S. FWIW I'm just contemplating my three gang switch box and how to handle the 8 grounds (5 cables and 3 screw terminals). One option would be loop a ground around each of the 3 devices, and use a wire nut on the 5 ground wires. Another is to use 3 pigtails; joining the 8 ground wires would require splitting them into two groups and using two wire nuts with a jumper between them.
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If you are using a metal box, splice your grounds together and to the box. Don't put them on switches. The neutral of a multiwire circuit (two hots sharing a neutral) cannot be dependent on a device, but if you are looping wire like you describe, it's not

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My electrician seems to love looping the hot wire from one switch to another in a 2-gang box. Is this fully against code or just not advisable?
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The NEC is silent on the issue. Basically it is legal

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snipped-for-privacy@aol.com writes:

Could someone please explain to me then what is "illegal" about the "looping" that the OP is talking about?
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Maybe it isn't, maybe it is just considered a questionable practice by some (including some inspectors?).
Wayne (the OP)
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Could be a 2002 110.3(b) violation. I just checked the instructions on a box of NM-B and found it says to make connections at the end.
With some inspectors(I've heard of), that's is more than enough to fail an inspection
hth,
tom
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The Real Tom wrote:

Could you elaborate on what that section covers? Does it deal specifically with NM cable?
With conduit installations it's commonplace when running wires from box to box to simply leave a loop in each box and cut off some insulation from the loop and hook it around the screw terminal.
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Any NEC quotes are summaries, please read the code for yourself:
No, it's a general instruction: "Installation and Use of Equipment". You need to follow the manufacturer's instruction. If the manufacture says to only connect at the ends of insulated conductors, then you need to do so.

Can't say it's too common. Simple since other people I run into, and how I was taught, you cut, pigtail, and wirenut. If you are using a greenie, then just cut, and wirenut. Now with the free end goes to the ground screw.
The knawing of insulation in the middle of the wire run seemed to look lazy/unprofessional, so I'm guessing an inspector can hit you as a 2002 NEC 110.12 violation. :(
Remeber i'm still learning, so I listen to what hapens to other electricians and take note.
later,
tom
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I have switches like this, a single hot comes in, and it daisey chained from one switch to another without ever being cut. It is the ONLY time I have found a terminal screw used in my house. Everything else is BACK STABBED. :(
later,
tom
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OK, based on the comments so far, let me try to revise what I think I know about looping a wire around a screw terminal (and continuing to another connection):
1) It is not advisable to do this with an insulated conductor, although I'm not too clear on the reasoning. One thing that is clear to me is that if this is done, the requisite 6" of conductor should be left before the first looped connection.
2) It is advisable to do this with the EGC and the grounding screw of a metal box or strap, because it makes a neater, tighter installation.
So that still leaves me with the question of whether it is a good idea to do this with the EGC and the ground screw on a device. Specifically, for a light switch, I'm considering looping the EGC of the cable with the outbound switched hot around the ground screw of the switch that serves it. What's the downside?
Thanks, Wayne
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As long as you remove a suffucuent length of insulation without nicking the wire, it is hard to see ant downside. It should actully be very slightly preferable as the total resistance to the last device on the line will be slightly less. Each junction adds a little resistance.
On Mon, 14 Mar 2005 11:52:01 -0600, Wayne Whitney

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Maybe naive question, but does "back stabbed" imply some particular kind of wiring (defect?), and if so, what is that?
Thanks,
David
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David Combs wrote:

Many residential grade (cheap) wiring devices have holes where a 14 gauge solid wire can be "stabbed" in and a spring clamp will hold it in place. It's a labor saving feature that can result in intermittent connections.
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On Tue, 12 Apr 2005 22:44:32 +0000 (UTC), snipped-for-privacy@panix.com (David Combs) wrote:

"back stabbing" is what I call when you strip the wire and push through the tiny holes in the back of a device(switch, receptacle, etc) that only uses spring pressure to hold onto the wire. So all you do is stab it into the hole.
This is different from what I call 'back wiring' where you insert the wire into the back, under a pressure plate and tighten a screw.
hth,
tom

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technical term for arcing and flickering of lights, applances, etc....
thx,
tom
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Scary things those.

Backwiring was described to me as the act of bending the ground wire back over the cable sheath, and using the box clamp to "make the ground" connection.
Ick.
--
Chris Lewis, Una confibula non set est
It\'s not just anyone who gets a Starship Cruiser class named after them.
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Back stab connections are legal. However the perspective is human safety. Code is only concerned with human safety. You have other concerns beyond human safety. Concerned not addressed by code.
Intermittents created by back stab connections do not adversely affect lights. But they can be catastrophic to computer data. Notice the difference. Back stabbing is just fine from the perspective of human safety. But a disaster for data safety. Perspective.
David Combs wrote:

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