stuffing electrical boxes

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Is there a trick to stuffing the caps and wires into an electrical box? So far I've done a few outlets with junctions (3 x 2 x 2.5 box, one 14-2 cable in, one 14-2 out, 3 caps, 1 one-inch duplex outlet with pigtails) and my fingers hurt.
I've left seven or eight inches of free cable inside each box (six is the required minimum but the guide says to go with eight if possible) and the pigtails are about three inches, and I'm using Marette 331 caps (not so big). I've tried folding the wires accordion-style in advance of connecting the outlet and that helps a little, but I still feel like I'm cramming the stuff in.
Also, I keep thinking the inspector will come in and say, "Why did you connect this outlet to that circuit? You should have run them this way instead." It's not a bad layout (I used to design printed circuit boards for a living) but I could have used shorter runs if I hadn't been particular about serving each corner of the space (two rooms in a 26 x 10' area) with each of two circuits. As long as I have a fair distribution in each room and observe the technical requirements, does the inspector care which circuit goes where?
I think I'm suffering from Inspector Anxiety.
-- "For it is only of the new one grows tired. Of the old one never tires." -- Kierkegaard, _Repetition_
James Owens, Ottawa, Canada
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You should have consulted article 314 of the National Electrical Code prior to the installation of your outlet boxes. By code definition they are too small. Table 314.16(A) tells you that you are allowed six number 14 conductors in the box. However you must deduct two from that total for each wiring device (Outlet) in that box and also deduct one wire for an internal wire clamp. If you used a connector that has its clamping mechanism outside of the box (Such as a romex connector) then no deduction for a clamp is necessary. Fortunately the ground wire only counts as one regardless of the amount. The pigtails don't count, but they sure do add to the space.
You should have used 3.5" deep boxes which is permitted to have nine number 14 wires. You wouldn't have had any problem "Stuffing" the wires, pigtails, and outlets into deeper boxes and you would have been code compliant. If depth was a concern, you could have used 4" x 4" x 1.5" square boxes with plaster rings based on the depth of your finished wall.
Plastic outlet boxes tend to have more volume than the metal outlet boxes. They usually have the cubic inch volume stamped on them.
I don't know what guide you used, but you should have picked up a copy of the National Electrical Code (NFPA 70) also. You can get it on Amazon.
John Grabowski http://www.mrelectrician.tv

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John, by my code book (Canada), he is allowed four conductors and four nuts, and he meets that. The code book I use accounts for the internal clamps and the duplex receptacle already. Are you using pigtails on the ground as well? If so, and if this is a duplex plug, you could leave one of the romex ground wires long, wrap it around a box ground screw, and then attach the distal end to the ground screw on the plug. The other ground wire can wrap around another ground screw on the box so you don't need the ground pigtail. Just be sure you have only one wire wrapped around one screw, as 'doubling up' on a screw is a no-no.. Electricians in my country do this all the time, and you would only need two nuts to fill the box. Get used to the sore fingers, it's the price you pay to enjoy manual labour. Just to clarify, I am not an electrician and do not know all the details of US code.
Dave

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"Dave" ( snipped-for-privacy@newsgroup.shaw.ca) writes:

Thanks. I'm using a pigtail for the ground. The book I'm working from is explicit: the bonding wire goes first to the box, next to all the other bare wires, third via pigtail to the receptacle. So that's the way I'll do it -- just call me chicken. :-)
It isn't explicit about whether, if there are two bare wires coming in, only one of them should go to the box. The text doesn't say, but the picture shows it that way. I've taken the incoming cable (from source) to the box, but there are two screws -- I could connect the other bare wire to the box before the pigtail. Would that be a good idea or not?
Also, about "wrapping around" the screw, is a complete 360 needed, or a 270, or is it OK just to run the wire under the screw at one side?

I was afraid of that. Thanks.
-- "For it is only of the new one grows tired. Of the old one never tires." -- Kierkegaard, _Repetition_
James Owens, Ottawa, Canada
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James Owens wrote:

If you don't have many to do, you might look for some ready-made pigtails made with stranded wire.

Wrap it around as much as you can without it overlapping itself. I generally go 270 if the wire stops at the screw, or 180 - 200 if the wire is wrapping around the screw and then continuing on to the device.
BTW, your 2x3x2.5" box should be fine for two #14 cables and a device. It's marginal (and probably too small) for two #12 cables and a device.
Bob
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First a general comment: If a box will contain a device (outlet or light switch), in particular a big device like a GFCI or a locking or dryer outlet, I would use a bigger and deeper box. My favorite is the 4x4 inch square box with a ring on it. If you need extra room, you can buy them in 2 1/8" deep, This means all the wiring mess can be on the two sides, leaving a "nest" in the middle for the device.

Highly recommended. They are a red wire nut, with a green, white or black pigtail (stranded flexible 12-gauge), and a real spade connector. You can take all the solid wires, neatly make them up (connect them together), and arrange them tightly in the back of the box. Then the pigtails for the outlet (or switch) stick out neatly into the middle of the box. The whole works looks pretty, and impresses the inspector. After he's done with rough inspection, it is super-easy to connect the outlet after drywalling, without having to mess around in the big spaghetti nest in the back. Unfortunately, they are not dirt cheap (a few $ for a bag of 10). Clearly, the inspector will know that this job was done by an amateur (I bet professionals are too cheap to use them, and experienced enough that they can do a neat job even without them), but the inspector will know that anyhow.

I think what you're describing is: One ground goes to one grounding screw on the metal box. Another ground goes to another screw on the same box. I'm not sure that this is legal. Here's why: The NEC says that grounding (or neutral for that mater) must not be interrupted if you remove a device. So it is illegal to use the two neutral screws on an outlet as a "distribution point" of sorts. Now, the box is not a device, and would not be removed, but I worry that using the sheet metal and two gronding screws might be pushing it.
The following, however, is OK: Take the incoming ground and leave it really long (maybe 15"), wrap it all the way around the ground screw, and tighten it. Now use one of those special wire nuts with a hole through the middle (I've heard they are called "greenies"), and use it to connect the other ground wires to this ground wire. You still have a few inches of pigtail sticking out of the wire nut, which you can now use to connect to the outlet. I think this is OK (one of the professionals might disagree, or bless it), and the most efficient way to handle the ground.
I think the continuity reason is why you are not supposed to do the same trick (wrap the wire around a screw and let it continue on) with the neutral or hot wires: If someone removes the device (outlet) with a pair of wire cutters, they would destroy continuity of the circuit. If this is really correct, I would conclude that a device shall have only one wire connected per pole, and pigtails are needed whenever there are more than two wires for the same connection. This is what the building inspector told me when I talked to him on the phne (inquiring about changes in the most recent code).

No, one allowance per INTERNAL clamp. One clamp can handle one or two cables. The internal clamps can usually two. The external metal ones (two screws, put into a round 1/2" knockout) can actually handle two 12-2 or 14-2 cables, but that seems so hokey to me, I try to always run only one.
The plastic ones that go into knockouts are always labelled on the box or bag as to what combinations of cable they can handle. I don't like using those at all, because they don't seem to grip the cable tightly, and if you check whether they are tight and yank on the cable, you can actually damage the white jacket on the Romex. So I only use them if space is so tight that I can't tighten the screws on metal clamps. Do they need an allowance? Beats me. Technically, they are outside (you push them into the knockout from outside). But they are not really outside the box (most of them sticks inside), so I give them one, just in case. I don't even want to know whether the clamps on plastic boxes require an allowance or not. First, I don't like plastic boxes much, they are not sturdy enough for outlets in my box (they are suitable for light switches and smoke detectors, at best). And second I won't use them where the fill is even close enough that the clamps matter; they are too hard to stuff.
The metal clamps always go outside (the screws are outside), and don't need an allowance. They are actually the only clamps I really like. They look sturdy, and hold the cable well.

Don't know whether it is required. But they actually make clamps for this purpose. They clamp onto the EMT with a setscrew, and then have a cable clamp (like the clamps described above) for the NM. I just installed one; they're available at either Home Despot or Lowe's. Makes it look very pretty.
For deburring the EMT: There is a tool plumbers use for deburring. About the size of a tennis ball, it is an external and internal reamer. Very convenient. While we are on this topic: From painful experience, don't use a plumbers pipe cutter (the ones with a rotating round blade) on conduit! They really neck down the cut, and leave a very sharp burr on the inside of the conduit. If you use one of these, you'll have to spend 5 minutes reaming and filing the conduit. It is much easier to use a hacksaw, and then quickly debur the cut with a few strokes with a file or a reamer. When taking out the old wiring I did 8 years ago, I found one EMT that I had obviously cut with a pipe cutter and forgotten to ream. The wires inside the conduit had shredded insulation and copper showing. I'm amazed I didn't get a short or ground fault at that point. Scary.
WARNING: I've not had my current job inspected yet, so my advice might be all nonsense. I'll let you know what the insepctor says ... if I still have electricy at my house after he red-tags me :-)
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_firstname_@lr_dot_los-gatos_dot_ca.us wrote:

I'm pretty sure you could use the hot screws/terminals on the device as a distribution point. If you destroy the continuity of the hot conductor be removing the device, it's not a safety issue. So connect the incoming black wire to 1 hot screw and the outgoing black wire to the other hot screw and you've eliminated a wirenut and a pigtail. You just can't do the same with the neutral nor the EGC.

Good luck with that.
Bes regards, Bob
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_firstname_@lr_dot_los-gatos_dot_ca.us wrote:

With respect to the neutral, Section 300.13(B) of the 2002 NEC says continuity must be maintained with the removal of a device, but it only applies to multi-wire branch circuits, i.e. 240V/120V circuits. Is there something in the NEC that would require this for 120V-only circuits? I've wired all my (backwire screwclamp) receptacles with out pigtails on the neutral.
Cheers, Wayne
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Wayne Whitney wrote:
> I've wired all my (backwire screwclamp) receptacles with

I did the same thing and the inspector passed it, and I was wondering if I should redo the neutrals.
In one box, I had 3 wires on each side of the backwire screwclamp devices (they had enuf back terminals for 8 wires) and the inspector said I had too many wires on one device and he made me change it.
Bob
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writes:

The first house I rewired, I noticed that the electician had done it the way I describe above. I wondered if it was against code, because I followed those diagrams exactly, as you did (those code books are similar between provinces). Then the second house I rewired, I noticed that the electician had done it as above as well. This is common practice when there are only two Romex wires going into the box, and it evidently meets Canadian code. I searched the Alberta code book for an explanation, and found a sentence that describes and approves the above pattern.
Remember that for this configuration, all ground wires first go to the box. If there are more than two then you definitely do need a pigtail, because there aren't enough ground screws in the back. No more than one wire per screw is a critical point.

It seems redundant if you are using a pigtail, 'suspenders and a belt'. But you won't get a complaint about that at inspection, and I suspect it may be marginally safer. I have always had a habit of doing it that way in the interest of safety. By the way, I like the long 8" wires you are using. For sure, don't use anything less than 6".

Go around at least 270, use needle nose pliers to pinch it around the screw, then screw the nut tight.

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Interestingly enough, I read the Knight book somewhat differently (at least an older one).
The Knight book doesn't seem to trust the connectivity between ganged boxes that much.
So this is how I do my grounds:
- The feed ground is left very long. - connects to a screw in each ganged section. - thence to each ground terminal on the devices in the box (almost never more than one. The switches I use don't have ground screws on metal boxes) - the final end wirenuts to the rest of the ground wires (feed thru).
When pushed to the back of the box, takes up almost no room, no pigtails required.
With hot wires, I "slide" the insulation for each screw, and can attach to multiple switches that way, only needing a wirenut if there's a feedthru unswitched hot. Only rarely use the second screw of an outlet for feedthru.
For neutrals in a standard single outlet feed thru situation, I slide the insulation to connect to the outlet, and wirenut the end to the feedthru wire. On multi-wire (split-duplex) too.
I've had inspectors inspect lots of wiring done that way, never any trouble.
Almost never need to use pigtails.
--
Chris Lewis, Una confibula non set est
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writes:

For sure, multigang boxes need direct connection. I don't like those multigang boxes, screwed together with a flimsy screw. They seem rickety compared to a welded box. The box he describes is a single gang box, not multigang.

This seems fine.

This sounds like an interesting idea, and I think it would allow the necessary ability to remove a fixture without disrupting distal connections. I'm not so sure it is easier to do compared to pigtails, and you don't save any wirenuts. With this plan if you remove a fixture and turn the breaker back on, you need to tape the bare section of wire to prevent fire (wirenut won't easily fit on a bare segment of wire with no end.)

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True enough. But I don't think I've ever wanted to power up a circuit once a device is removed in this fashion.
I usually don't do that trick with the hot on a simple passthru connection for an outlet either.
But it makes a huge difference with workability on wiring ganged switches.
I usually arrange each fixture's feed to the top of the ganged box, arriving in the box where its corresponding switch is going to go. The power feed comes in the bottom at one end of the gang. [I almost always have the unswitched power going to the switch box, rather than using switch loops.]
Route the feed grounds under one box screw per gang, then wirenut to the fixture feed grounds. Push back flat against the back of the box.
[If you have multiple devices requiring grounds, you can route the ground just like the black below.]
Wirenut all the neutrals together as usual and lay in.
Then, strip the black feed in multiple places, and string the switch bottom screws to it. If I have a hot feedthrough to elsewhere, wirenut that. So now I have the hot wire hanging out with all of the switches strung on it. Attach the corresponding fixture blacks to the other screws, and bolt the switches in.
Once finished, it's surprising how _little_ room in the box is taken up by wire. And identifying which wire/cable is which is trivial - easy to rework things later.
I wish I could show pictures, but I don't have good samples around here that are accessible. I'd have to fake it. Then find somewhere to post it.
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Chris Lewis, Una confibula non set est
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Chris Lewis posted for all of us....

--
Tekkie

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Thanks. I'm working to Ontario code and I have carefully read a simplified guide, last updated 2003, with box fill tables that let me do this. There's even an illustration that shows basically the boxes I'm stuffing, and it says to use 2 x 3 x 2.5 for the job. In my several trips to Rona (the Canadian equivalent of Home Depot) I have never even seen a box 3.5" deep. (I did pick up some 3" deep boxes for junctions containing a switch.)
Running a cable into and out of a box with a receptacle in it has got to be a fairly routine thing -- practically unavoidable. You don't mean they require 3.5 deep boxes in the States? (If so, they must be easier to stuff!)
BTW, in the Ontario code, the bonding wires don't count in the box fill calculations. For those purposes I have only four wires. The loomex cable clamps are built into the box, at the back.
"John Grabowski" ( snipped-for-privacy@optonline.net) writes:

-- "For it is only of the new one grows tired. Of the old one never tires." -- Kierkegaard, _Repetition_
James Owens, Ottawa, Canada
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A 3 1/2" deep box would be difficult to use on 3 1/2" deep 2" x 4"s, especially with ground screws and clamp screws sticking out the back. That means the drywall would be hitting, and pressing on the back and could cause the screws to pop a hole through the drywall. They would be fine for 2" x 6" studs.

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Eric Tonks wrote:

equal to the thickness of the drywall installed, or to be installed, usually 1/2". Therefore there is a 1/2" gap between the back of the box and the opposite side drywall.

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willshak wrote:

I should have checked my shop first. Apparently, like lumber, they use nominal sizes for electrical boxes too. I have a 3" blue plastic box, that when measured is actually 2-7/8" from front to back (outside measurement). I also have a 3-1/2" (20 cu in) tan plastic, 2 hr fire rated box that when measured, is 3-1/4" from front to back (outside), so the gap between the back of a 3-1/2" box and the opposing drywall in a 2x4 studded wall would be about 3/4", after allowing for the face drywall projection.
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I always use stranded wire because I don't have all these problems pushing the receptacle or switch back into the box. The only reason why Romex is even used is because it's slighly cheaper than stranded wire, and home buiulders are penny pinchers. Always buy the receptacle/switch box that you can put in a given location. My biggest gripe on boxes is that if you like the metal ones like I do (I would never use a plastic box) then it's either a "switch" box that isn't tall enough or a "handy" box that isn't deep enough. At least you get to pick which direction you want to be constricted in.
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It's best to always use the deep boxes (eg: 3") except when you simply don't have enough depth for it. Your fingers will thank you.
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