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Discussion Starter · #1 ·
Hi All - I recently remodeled the downstairs level of our split level home. When doing so I ran a few 12/3 (white/black/ground) from my electrical panel into my crawl space for future plans.

Its come time that I need a couple of outdoor receptacles. One in the front of the house one in the back. I also want to put up probably three motion sensor flood lights.

I have many more questions but we'll start here.

Can I run those items all off the same 12/3 line?
 

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How many watts for the floodlights. Really high powered tungsten halogen lights would probably mean you need a separate circuit for the three of them.
 

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yeah, do a load calc....but if i recall correctly i think no more than 10 fixtures/outlets on any circuit...i'm sure someone can give the exact NEC reference. but that is really a basic guidance and load calcs should always be done.
 

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First thing is you don't have 12/3 you only have 12/2. 12/3 has a red wire. The ground doesn't count.
There is no limit in NEC about the number of device on a circuit. Unless you have some hogh wattage lights then there should be no problem with all them on the same circuit.
 

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Discussion Starter · #5 ·
Thanks - I haven't bought the flood lights yet but probably look at 300w lights.

Its acceptable to run the three lights and two receptacles off of the one 12/2 wire?
 

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Three 300 watt light fixtures for 900 watts out of the available 2400 watts (20 amps). THis is borderline. Most of the time you would not have a problem with the two outlet boxes on the same circuit, but there may be times at night when you don't have enough power and you trip the breaker.
 

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Per NEC you can only load a circuit to 80% which comes out 1920 watts.
Which is 16 amps
3- 300 watts lights equals 7.5 amps.
Since yiu know how many outlets you are adding, than load calc is 2 outlets x 180 va= 360 / 120- 3 amps
3 +7.5= 10.5 amps
You will be fine.
 

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Per NEC you can only load a circuit to 80% which comes out 1920 watts.
Which is 16 amps
3- 300 watts lights equals 7.5 amps.
Since yiu know how many outlets you are adding, than load calc is 2 outlets x 180 va= 360 / 120- 3 amps
3 +7.5= 10.5 amps
You will be fine.
That is false. A 20 amp circuit can be loaded to 20 amps. The 80% rating is for continuous loads of 3 hours or more.
 

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Discussion Starter · #9 ·
Thanks - I'm actually going with either two or three 200watt lights for the outside plus to
receptacles
.

Now how do I split all of these things off from my one 12/2 wire?
 

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Are you running power to the switches first or the receptacles? How many switches? Will the receptacles always be on or switch controlled?

I might suggest you read "Wiring Simplified" so you can see some wiring methods.
 

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Discussion Starter · #11 ·
Are you running power to the switches first or the receptacles? How many switches? Will the receptacles always be on or switch controlled?

I might suggest you read "Wiring Simplified" so you can see some wiring methods.
Hmm excellent question! I haven't really thought about having the receptacles on a switch. If I do have switches I'll have one for each of the two receptacles.
 

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Discussion Starter · #12 ·
Getting back to this thread... I'm going to forgo the security lights for now and focus on the one outdoor receptacle. I'm going to get the following:

http://www.amazon.com/gp/product/B000NCTJ4I/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

http://www.amazon.com/gp/product/B0038OMTH2/ref=ox_sc_act_title_2?ie=UTF8&m=ATVPDKIKX0DER

I have questions on how to run my 12/2 wire which is in the crawl space and goes directly to the breaker box. Now most of my wiring is going to be through the crawl space so I can get a receptacle in the front of my house.

Now I have my 12/2 wire in the crawl space towards the back and there's not much slack. So I think I need a junction box right by that 12/2 wire which allow me to run the actual wire to the front of the house.

What type of junction box?
what type of wire?
I'm going through brick, what do I need to do here?
 

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Now I have my 12/2 wire in the crawl space towards the back and there's not much slack. So I think I need a junction box right by that 12/2 wire which allow me to run the actual wire to the front of the house.

What type of junction box?
what type of wire?
I'm going through brick, what do I need to do here?
Is the crawl space dry and sealed up with a concrete floor?
 

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Since you said the crawlspace is dry you could run NM-B and use plastic nail-on boxes with blank covers. Drill a 1/2" hole thru the brick and come into the back of a weatherproof box. You will need to chip out the brick face for the connector that gets screwed into the back of the box. Caulk the top and sides of the box to the brick. Install a weather-resistant GFI and a weatherproof in use bubble cover.
 

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Discussion Starter · #17 ·
Since you said the crawlspace is dry you could run NM-B and use plastic nail-on boxes with blank covers. Drill a 1/2" hole thru the brick and come into the back of a weatherproof box. You will need to chip out the brick face for the connector that gets screwed into the back of the box. Caulk the top and sides of the box to the brick. Install a weather-resistant GFI and a weatherproof in use bubble cover.

I can use a box like so?

http://www.amazon.com/Carlon-B520AR...?s=lamps-light&ie=UTF8&qid=1315840810&sr=1-14

Do I need to run my NM-B wire through PVC or is drilling through the joists and running it ok?
 

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Discussion Starter · #19 · (Edited)
Makes sense --- here's what I got so far.

http://www.amazon.com/gp/product/B000NCTJ4I/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

http://www.amazon.com/gp/product/B0038OMTH2/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

I think I'm going to go with the UF cable just for some added piece of mind.
http://www.amazon.com/SouthWire-Company-13055922-Wire-50-Foot/dp/B000VHDRDO/ref=pd_cp_hi_2

Also the junction box (for lack of a better word) can accommodate multiple UF connections if I wanted to maybe add another outlet in the back of the house?
 

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Makes sense --- here's what I got so far.

http://www.amazon.com/gp/product/B000NCTJ4I/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

http://www.amazon.com/gp/product/B0038OMTH2/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

I think I'm going to go with the UF cable just for some added piece of mind.
http://www.amazon.com/SouthWire-Company-13055922-Wire-50-Foot/dp/B000VHDRDO/ref=pd_cp_hi_2

Also the junction box (for lack of a better word) can accommodate multiple UF connections if I wanted to maybe add another outlet in the back of the house?
Looks good. UF is a waste of money here IMO. PITA to strip also. Only 1 cable per clamp, box fill applies
 
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