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firemanpato 01-05-2008 05:56 PM

Wiring diagram, would this work
First off, great boards. Lots of good info.

Second. This is a homeade (not quite professional quality but close!!!) wiring diagram of my basement. The black lines are existing 14/2 wire and the red is what I propose to do and the green is a 14/3 wire so I can control the lights with 2 different switches. The circles are 6" recessed lights with 75 watt bulbs.

The black is what I currently have. One 14/2 wire out of the breaker box on a 15 amp circuit and it controls 4 lights. I want to steal some power from the last switch and run it to a 4-gang box (all the red wires) and run 3 sets of lights. Then I want to take a 14/2 wire from the 4-gang box, run it to the last switch to power the last 2 lights in the corner and the lone outlet.

Will this work???? Are there too many lights for a single 15 amp circuit. I can't add more circuits so that is why I hope I can run it all off the existing circuit. Oh, and the most lights that will be on at any given point will be 10 maximum. Rarely. Mostly will just have 6-8 lights on.

Any help or suggestions would be greatly appreciated.

gregzoll 01-05-2008 07:55 PM

Does it exceed the Rule of 12 (switches, outlets, lights, etc) for that circuit? I counted 23 devices aprx. on that one circuit. I would say yes, especially for 14/2 wiring.

joed 01-05-2008 08:01 PM

It will work just fine. You have one extra cable that is not needed. The two lights you want to control by the three way only need to connect to one of the switches. You can eliminate one of the cables from a fixture to a switch.

I do think you are close to having too much on that circuit. It depends on what you intend to plug into the receptacles. A 15 amp circuit has an 1800 watt limit. Also if you were in Ontario you have a limit of 12 outlets per circuit. An outlet includes receptacles and light fixtures.
Consider connecting only the bottom two new lights to the old circuit and running a new circuit for the upper portion of your drawing. Depending on what you intend to use the receptacles for maybe consider putting them on a separate circuit and leave all the lights on the old circuit as long as you stay below the 1800 watt limit.

Also steal the power from the first switch or a new breaker. It is closer and shorter cable run.

firemanpato 01-06-2008 12:59 AM

Thanks for the information. Very helpful.


Here is a new simple diagram (once again the quality is excellent)

The red wire is 12/2 running to the new lights on a 20 amp circuit and the blue is 14/2 running the two lights seen and an additional 4 lights in the basement on a 15 amp circuit. The black box on the left is the breaker and the big box on the right is a 4-gang box.

My question. How many wires can you safely have coming out of a 4-gang box?? Also, can you have one switch in the box controlling the lights with 14/2 wire and the rest of the switches with 12/2 wire controlling everything else??? The 12/2 and 14/2 wires will not be connected in any way. They will just be in the same box connected to different switches. Is this ok???

Thanks again for the help.

LawnGuyLandSparky 01-06-2008 08:54 AM

You can have more than one circuit in a box. The 4-gang switch location will have embossed a cu. inch inch rating inside the box. Suffice it to say, if you have a 2-wire feed and 4 x 2-wire switchlegs and a 2-wire feed out, you won't exceed the box fill.

As for your diagram, you can't feed outlets off the lights without the outlets turning on and off with the lightswitches.

J. V. 01-06-2008 12:46 PM

There is no limit on residential receptacles in the NEC. You can put as many recepts as you want on 15 and 20 amp circuits. The only requirement is that the correct size conductors be used for the breaker.

joed 01-06-2008 02:26 PM

Unless you have some 14/4 cable you are not going to be able to make the blue three way setup work. Four wires + ground are required between the lights to make that drawing work. You should go sw=light= sw with 14/3 and then light-light with 14/2.

firemanpato 01-06-2008 05:19 PM

New updated picture
Ok, here is the latest. This is what I am planning on doing.

The right side is one circuit using a 20 amp breaker with 12 gauge wire going from the panel to all the 15 amp outlets and then to the switch box to power the 3 sets of lights on 3 different switches.

The left side would be a separate circuit with a 20 amp breaker and 12 gauge wire going to 2 20 amp receptacles and then to the switch to power the one set of lights. The reason for the 20 amp outlets is an engraving machine I have that always trips my 15 amp outlet.

Does anyone see a better way of wiring this?? I need to keep the outlets on different circuits because the left half (blue boxes) are the 20 amp outlets for the engraving machine and the right half (green boxes) are for the home theater/ family room setup.

I also want to keep the whole area to 2 circuits. I could go... outlets on 2 different circuits and then lights on a single circuit, but would prefer 2 instead of 3 circuits due to limited breaker box space. But 3 would work if I had to.

Let me know what all of your opinions/insights are. Thanks

chris75 01-06-2008 07:35 PM


Originally Posted by gregzoll (Post 85901)
Does it exceed the Rule of 12 (switches, outlets, lights, etc) for that circuit? I counted 23 devices aprx. on that one circuit. I would say yes, especially for 14/2 wiring.

What is the Rule of 12? What code section are you referring to?

gregzoll 01-06-2008 09:02 PM

It is more of a Rule of Thumb, to not allow any more devices then a Circuit can nomially handle.

joed 01-07-2008 05:33 PM

I would route the power to the red circuit to the switch box first instead of through all the receptacles then the switch box.

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