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-   -   Is this okay? 4 switch box (http://www.diychatroom.com/f18/okay-4-switch-box-19898/)

helpless handyman 04-14-2008 07:51 AM

Is this okay? 4 switch box
 
Hi, I have a 4 switch box where I will be installing 4 switches, 3 to Halo high hats, and one to sconce lights.. I have 2(Halo) lights coming into the box for switch-1, another 2 (Halo)lights coming into another switch-2, and 2 more halo lights coming into the the third switch. I also have 2 sconce coming into this box as well. I want to be able to control all the light, instead of having one switch lighting everything up. Most likely all these lighs will never be on at the same time. The Halo will have 13 watt energy bulbs on them, the sconce will have 13 watt bulbs as well. My question, I am feeding the 4 switch box with a 12/2 on a seperate circuit, can I tie onto this 12/2 as well to do 2 more halo high hats in the laundry room? Total on one circuit, 8 halo (13 watts) and 2 sconce 13 watts giving me a total of 130 watts. Thanks guys. Also how many wires can one tie together in a box this size? I was planing on tieing all the neutrals and pig tail the hot that will be feeding the switches?
** This will be on a 20 amp circuit**

HandyPete 04-14-2008 08:29 AM

This is a touchy question because there's more to it than you think. I can say this..

20A circuit and #12awg is fine. The total wattage for that breaker should be no more than 2000 watts. Now for your box....

First, I hate 4 ganged switches, after awhile they get too confusing to use. Second, it needs to be really big with all those wires and connections you want to make. The Code is explicit with this, it specifies the size of the box for the amount of wires and how many wire-nuts there are. Don't ever think of cramming stuff together when doing wiring, we electricians like lot's of space and air!

- pete

helpless handyman 04-14-2008 08:59 AM

The box is pretty big and deep as well. The electricians used this same box upstairs where they did 3 way switches on each end of the room. They are gone and that's why I am asking.

WoodworkerDave 04-14-2008 09:12 AM

I'm not an electrician, but I have been dealing with NEC box volume calculations in a workshop wiring project I'm working on. For 12 gauge wire, you need 2.25 cubic inches of box space for every wire that goes into the box. Plus, each light switch counts as 2 wires and requires an additional 4.5 cubic inches of space. The equipment grounding wire is counted only once, needing 2.25 cu in. Although probably not applying to your situation, any wire that merely passes through the box without terminating (and has less than 12 inches of length within the box) counts as one wire, requiring 2.25 cu in. Any wire that is contained completely within the box (does not enter or leave) does not count.

So assuming each of your 4 light circuits plus your infeed cable have one hot and one neutral, that's 10 wires there. Plus 8 more for the switches and one for the ground. A minimum of 19 wires (more if your box is wired differently). 19 x 2.25 = 43 cubic inches of inside box space minimum. As was said previously, more space is always better.

Silk 04-14-2008 09:13 AM

Nobody can answer your question until you state the cubic inch capacity of your box and the number of cables or wires entering your box. If the box is plastic it will be stamped on the inside back.

HandyPete 04-14-2008 09:16 AM

One other tip....

Ideally, you want the feed wires (hot and neutral) to come to the switch box. It's also better to have just one wire from each lighting circuit in the box, the junctions to multiple lights should be in other boxes or at the fixtures.


- pete

helpless handyman 04-14-2008 09:20 AM

Okay, I will check to see the size of the box. Like I said previously, the electricians used on the kitchen dining area as well as the living room. They are 4 switch boxes with 3 way switches on them with to me would be more wires that what I am using. It's not a plastic box, it a 4 switch box metal, and if they made it bigger, it wouldn't fit between a 2 x 4 . Thanks

jrclen 04-14-2008 10:45 AM

A typical 4 gang plastic (pvc blue) switch box is 60 cubic inch. That would give you plenty of room to comply with the electric code with the wires you mentioned. So if that is the box you have, it will work just fine.

When calculating the load on the circuit, use the maximum rated bulbs listed in the fixture instructions and not your 13 watt lamps. If the fixtures are rated for 60 watt bulbs use 10 x 60. If they are rated for 100 watts use 10 x 100. The reason for this is the next guy who comes along might change bulbs. In either case, a 20 amp circuit will be more than adequate for your 10 fixture load.

Connecting all the neutrals with the proper sized wire nut and pig tailing both the grounds and hots to the switches is how it is done. You are good to go once you verify your box size.

Ganging 4 switches in a box is very common and no problem at all.

frenchelectrican 04-14-2008 01:22 PM

Let me add one more thing here you may not well aware that pretty good percentage of CFL screw in bulbs are useally nonworkable with dimmers and becarefull some of the CFL are not rated to run inside of the recessed luminaires at all.

with 4 gang switch box it pretty common almost everywhere both resdentail and commercal location.

but a quick head up you may want to make a support behind the 4 gang box some dont have very good rigid support so take either patom [ ghost ] stud or use a brace [ some 4 gang box or larger will have this included ]

Merci,Marc

helpless handyman 04-14-2008 01:47 PM

Thanks, box is braced on both sides with studs, and I am aware of the no dimmers on flourescent bulbs:thumbsup:

Leah Frances 04-16-2008 09:37 PM

Idle thought: my parents put a four-gang in their hallway twenty-five years ago. I lived in the house 15 years and still only know, for sure, that the first switch turned on the hall light. As for the other three: flip and test, flip and test, flip and test, until I get the light bank I wanted.

jrclen 04-16-2008 11:39 PM

Quote:

Originally Posted by Leah Frances (Post 116925)
Idle thought: my parents put a four-gang in their hallway twenty-five years ago. I lived in the house 15 years and still only know, for sure, that the first switch turned on the hall light. As for the other three: flip and test, flip and test, flip and test, until I get the light bank I wanted.

A sharpie will work for that. Color to match the decor. I admit it's hard to see with the lights out. :laughing:


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