Electrical Junction Box with Bus Connections

[Harry Muscle]

I'm going to be rewiring my house soon and because of the layout of my house, it looks like there's going to be a handful of areas where it will be easier to run a circuit to a junction box and then branch off all the connections for that ciruict from that one juction box. That means there will have to be around 12-14 wires comming in and all be connected to the supplying wires. This makes me think that a bus connection would work best, like the ones that exist in the breaker panel box.

So my question is ... does such a junction box exist? One that already has bus connections build into it? Also, is my idea up to code? I've studied the Ontario Electrical code and I don't see anything that would say that I can't do this ... as long as I don't overfill the box.

Thanks, Harry

[SQLit]

They are usually custom made. These boxes have to be accessible as well. Since your thinking of this you would be required to provide overcurrent protection for the smaller wires unless you are thinking using one of the tap rules, which as far as I know apply to feeders not branch circuits.

My lay outs are usually a 12or 14-3 to a box. I like to a use the smoke detector location. I use a deeper and larger box to accommodate the junctions.

Best to check locally to be sure before you dive off the pier....

[Chris Lewis]

According to Harry Muscle :

It'd be code, but as mentioned elsewhere, such junction boxes aren't available commercially, so you have to make them yourself.

You _could_ go to the trouble of using, for example, regular metal boxes and suitably rated terminal strips as the commercial/industrial electricians do. You'd be doing your own "custom boxes".

However, the equipment isn't officially certified for it, and you'd have to have unit-approvals (on _each_ one) done by Ontario Hydro (or whomever they suggest) at something like $75-$150 _each_.

It's usually better to utilize a string of ordinary (deep if necessary) J boxes (giving attention to the accessibility requirements) to cut down the number of wires in each box. The parts are cheap and rated for it. Just a bit more labor, and (perhaps) obnoxiousness w.r.t. accessibility requirements.

[Goedjn]

[Rod Nussbaumer]

I'm not an electrician, and I don't play one on TV, but...

Isn't there a rule that limits the numbr of 'devices' on a branch circuit? Something like a mximum of 15 switches and other fixtures per circuit? I'm assuming a 'branch' would be defined as a circuit protected by a single breaker in a panel. So, then, why wouldn't the original poster simply put in one or more sub-panels to serve the specified purpose. This would solve the problem, remain within code, and offer more conventional utility.

--- rod.

[SQLit]

Circuits are determined by load. In residential load calculating, a breaker will generally 80% supply of the rating on the breaker. Example, a 15 amp circuit is considered to be maxed out at 1440 watts.

Just wondering, how much power do your switches use? (humor implied)

[Kilowatt]

This is a very big mistake. Try to plan your junction boxes where there are no more than 4 cables in one box. Do this for two reasons. You need smaller boxes and you will never get wire nuts on anything larger.

You should not be putting 12-14 outlets on one circuit either.

[phil-news-nospam]

| Circuits are determined by load. In residential load calculating, a breaker | will generally 80% supply of the rating on the breaker. Example, a 15 amp | circuit is considered to be maxed out at 1440 watts.

I remember in my college dorm, the receptacle circuits were divided out serving 3 walls each. That is, 3 rooms would be split across 2 circuits. The end rooms of a set would be entirely on a single circuit. The middle room of a set would have half on one, half on the other. Lights were on another bunch of circuits.

For quite a while, the room with the circuit breaker panels was left unlocked (as side door entered through the laundry room). When a breaker got tripped, people would just go in and reset them. Apparently there was some abuse, and the door was eventually locked. The RA had the key. But the RA on my floor was too often not willing to go reset the breakers very quickly, and that was getting some people upset. He was blaming them for running too much stuff (which is partly true). Anyway, it turns out my room is next to the RA's room, and half of my receptacles are on the same circuit as all of his. So what I would do to help out was short the circuit in my room that was shared with his, and that would get him to finally get off his butt and go to the breaker room and reset things.