Home Electrical Question

[char]

So I was tracing circuits the other day and figured out that there are two separate runs of cable that come out of 1 240v 20A circuit breaker.

One circuit runs to an upstairs baseboard, the other to a downstairs wall heater. Both are 240v. When I pulled the cover on the electrical service panel I discovered that for each pole on the 240v breaker there are 2 wires connected.

2 questions:

Is this up to code?

If it is up to code, can I do it on another 240v breaker I have to add a heater in another room so long as I'm below the 80% rule on amps? This would allow me to go through my attic instead of ripping up a bunch of drywall in the basement.

[back bowl]

It all depends on the breaker. Square D makes a line of breakers that (QO series, I think) are approved to accept 2 wires under the screw, and I think there's another manufacturer that's similarly approved for double taps, but the Square D are the only one's I'm familiar with.

If you pull the breaker out and look into the receiver end of the breaker and the hole looks like this, you're probably good to go:

The receiver is designed for 2 wires.
Anything else is wrong, but can be corrected by replacing the breaker with one that's approved for two wires in the receiver.

[Beaver]

Not to code. In the Canadian Electrical Code (essentially the same as the US one) even if you have a breaker that looks like it was designed for 2 wires you're not allowed to make a splice within a breaker panel box. That is considered a splice. CEC 6-214

To make code, come off the breaker with a 2#12 then out of the panel to a junction box. Make your splice in the JB and you're to code.

[char]

So thats one yes and one no.

Anyone else have an opinion? Looks like I should probably call the building department.

Beaver- I'm under the impression that I can make that connection inside the panel here. One of the few exceptions to the rule of not using the panel as a junction box.

[Beaver]

Think about this when you make your connection. If one of those 2 wires is not perfectly in the groove pressure will not be even on each wire and one will heat up under load. Heat/cool/heat/cool.... over time will lead to trouble, trouble may be a fire, inspector will see non code electrical, insurance co will say "tough shit dude." If you must make the connection twist the wires together really well then stick them under the terminal and screw that fucker down tight, that way at least there will be equal pressure on both wires and you will not have potential trouble.

If you don't know phone your friendly local electrical inspector and ask him or call a local electrical engineer or contractor. Your impression may be wrong and it may never be a problem but it may come back & bite you in the ass. You could also go to the public library & look it up

[char]

Beaver-

I was talking about pigtailing the single wire off of the breaker to the splice and doing so inside the electrical panel as opposed to doing it in a separate junction box.

Thanks for the help!

[Beaver]

I asked an engineer in the office who has copy of the NEC and has worked in the USA. NOT TO CODE

[back bowl]

It falls back to the UL listing. If the manufacturer's instructions OK it and it's UL listed for two wires, it's OK by the NEC as per article 110.3(b).

Also, your pigtail within the breaker box is OK with the NEC as long as there's enough space in the box, as per article 312.8.

My caveat: that's based on my 2004 copy of the NEC... I haven't had to do this stuff since then, so things could have changed- but it's unlikely....

[whacked]

It's called double tapping and it's not code (NEC in the US). What you describe may well work just fine, but it won't pass. And I wouldn't want to debate some exception in the code with the inspector; you'll just end up doing it over.

[back bowl]

Maybe it's a regional thing, but out here it's commonplace and is OKed by inspectors all the time as long as you're using breakers that are listed for double taps. I'd start by getting the literature from the breaker manufacturer, probably download it off the website, then call your local inspector and ask. There's no harm in trying, and if your inspectors are like the guys out here (Vermont), they'll be well aware of what breakers are acceptable for a double tap and which are not...

[Crass3000]

How much current do they pull when on? I'd be a little leary of having all that heating on a 20A circuit even at 240V.

[char]

Yeah, I figured I should just ask the inspector, but it's MLK day and I was curious.

Crass- 12.5 amps total.

[spudbumkin]

As for splices in a panel, this is a wives tale long perpetuated by myth. Yes, it is very true that you cannot use a panel as a raceway for certain conductors, and splicing is illegal under certain circumstances, but pigtailing is absolutely legal, safe and accepted. Actually it is required in some cases to avoid double tapped breakers. The authority having jurisdiction (the inspector) has the final say and even then each individual one will have a different take than another. I say go for it, you will be alright.

[strawjack]

Maybe it's a regional thing, but out here it's commonplace and is OKed by inspectors...

regional thing and inspectors...it amazing how different things are from town to town let alone state to state. here pigtailing is common and doubling up not so much.

i'm with BB...call your inspector.

[Jethro]

As for splices in a panel, this is a wives tale long perpetuated by myth. Yes, it is very true that you cannot use a panel as a raceway for certain conductors, and splicing is illegal under certain circumstances, but pigtailing is absolutely legal, safe and accepted. Actually it is required in some cases to avoid double tapped breakers. The authority having jurisdiction (the inspector) has the final say and even then each individual one will have a different take than another. I say go for it, you will be alright.

Second this. I have been a licensed electrician since 1994 and have been to several convention courses where this issue has been addressed. You are allowed to pigtail loads together and extend wires with a wire nut in a panel. You are not allowed to junction wires in the panel which do not originate there. The panel isn't to be used a j-box or pull station

If you have the room, why not just add another breaker. It is legal to put two wires under Square D QO series breakers. "Double tapping is when two conductors are under one set screw, like you find in GE, Sylvania, ITE, Cutler hammer, etc panels.

[char]

I don't really have room to add another 240v breaker.

I'd like to get a bigger panel, but that costs more than I'm really willing to pay right now.

[Jethro]

The breaker is listed for two conductors per screw. I would take the two conductors currently under one lug and pigtail on a single wire to go to the lug. Does anyone here seriously think that the NEC would prohibit extending a wire? What would you do if a wire was to short and would not reach a breaker? You are allowed to pigtail and extend wires which originate in the panel. My code book is at work, or I'd post a code section.

Another solution could be to get some single pole double up breakers and make room for another two pole breaker.

If anyone has doubts, Google "Mike Holt" and go to his forum. He is a nationally recognized code expert and this has been addressed in his forum before.

[TWINS]

. It is legal to put two wires under Square D QO series breakers. "Double tapping is when two conductors are under one set screw, like you find in GE, Sylvania, ITE, Cutler hammer, etc panels.

QO series breakers are usually on Square D commercial panels.Homeline series is the residential garbage Square D tries to sell.I have never seen a QO panel in a residence yet.Anyways,just pigtail the 2 load wires together with a 12 guage single wire running to the breaker.
Or make space/add another 2 pole/20 for the other set of wires.
Our inspectors do not allow doubling up on breakers.

[Jethro]

You are right, Homeline is the cheap residential series which is compatible with the ITE type of breaker. Their stuff is still superior to the other makers though. Square D also makes 40 and 42 circuit and smaller main breaker and main lug panels which fit in a standard 14.5" stud bay space. They take the same QO series snap in breaker you see in 20" wide commercial panels. The other Commercial breakers are bolt in. As a 20+ year electrician, please believe me when I say they make QO panels for residences. A simple Google search of QO residential will confirm what I am saying.

Another thing to remember is that many inspectors have the same limited exposure as electricians. Often the way they are taught is what they expect of others, regardless if it is correct or the only way of doing things. If they do not allow doubling of wires in contradiction of the product listing, who do you think is correct, the inspector or the manufacturer?

[Chainsaw_Willie]

Each one of those heaters is only 6.25 amps???

[Snow Dog]

Or 1,500 watts (240V * 6.25A).

[spudbumkin]

I'll refer everyone to 312.8 of the 2011 NEC. It states that splices are acceptable in cabinets containing overcurrent protection devices, if said splices and conducters don't fill the space of the cabinet by more than 75%. I am just paraphrasing the actual code, one should get the NEC to get the exact verbage.

[char]

For my jurisdiction and electrical inspector:

So long as the breaker is rated for two wires per screw, double tapping is acceptable. Pigtailing inside the box is also acceptable.

Both are some what frowned upon because it is a quality of work issue. IE- In new construction double tapping would probably make him look at what else you didn't plan ahead for .

In remodels or repairs he said it wasn't an issue so long as everything fit. 75% rule.

-----

I have a Square D QO loadcenter in my house, so that isn't an issue.

Chainsaw- Roughly 1500w per heater. I'll have to pull the cover on the one downstairs to get the exact wattage. I'm not modifying that circuit though.

[Chainsaw_Willie]

Oh. Duh. Math>me.