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Author Electrical Junction Box with Bus Connections
Harry Muscle

2005-06-22, 12:25 pm

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

2005-06-22, 6:25 pm


"Harry Muscle" <fake.e-mail@stonyx.com> wrote in message
news:1119449043.700562.2XXXX0@z14g2000cwz.googlegroups.com...
quote:

> 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


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

2005-06-22, 11:25 pm

According to Harry Muscle <fake.e-mail@stonyx.com>:
quote:

> 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.

quote:

> 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.


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.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.
Goedjn

2005-06-22, 11:25 pm

On Wed, 22 Jun 2005 22:21:47 -0000, clewis@nortelnetworks.com (Chris
Lewis) wrote:
quote:

>According to Harry Muscle <fake.e-mail@stonyx.com>:
>
>
>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.


Rod Nussbaumer

2005-07-04, 6:25 pm

SQLit wrote:
quote:

> "Harry Muscle" <fake.e-mail@stonyx.com> wrote in message
> news:1119449043.700562.2XXXX0@z14g2000cwz.googlegroups.com...
>
>
>
> 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....
>
>


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

2005-07-04, 6:25 pm


"Rod Nussbaumer" <bomr@shaw.ca> wrote in message
news:Wueye.157400$El.155922@pd7tw1no...
quote:

> SQLit wrote:
the[vbcol=seagreen]
>
> 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.


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

2005-07-05, 4:25 am

Harry Muscle wrote:
quote:

> 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


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.

Roy Q.T.

2005-07-05, 4:25 am

Harry, you could probably use a Trough to handle the 12-14 cables
in/out, or a DIN rack in a sizable enclosure with appropriate sized
breakers & terminal blocks, but no such animal as a junction box with a
buss,. That would be a Subpanel.

Roy Q.T.
Urban Technician
[I don't make em, I just fix em]

phil-news-nospam@ipal.net

2005-07-05, 6:25 pm

In alt.engineering.electrical SQLit <sqlit@qwest.net> wrote:

| 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.

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