[abcsalem]

I like to install 4 sets of flood lights. Each set is a pair of 150 watts bulb, for a total
Of 300 watts per set, for a grand total of 1,200 watts for all 4 sets.
Can I put all 4 sets of flood ligts on a 15A circuit?
This is the way I like to install them: 2 sets of flood lights for the back yard,
And 2 sets for the front yard. On some occasions, all 4 sets of flood lights
May be turned on all at the same time for several hours. On some other occasions
Only 1-2 sets of front yard or the back yard will be on.

These flood lights will be installed under the eves, with wires coming from the
Basement to the attic. I was planning on using 12 gage wire, and use two 15A GFCI
Breaker, one for each 2 sets.

My main breaker is 200A, total load is ~ 90A
I have a 100A subpanel that I was planing to install these breakers in.

What would you recommend?

Thanks in advance

[hkstroud]

The total for all four sets of lights, 1200 watts, is only 10 amps. Can all be on one 15 or 20 amp circuit. Why a sub panel? If you use 14 gauge wire you must use 15 amp breaker. If you use 12 gauge wire you can use 20 amp breaker or 15 amp breaker. This is true whether you run one circuit or two.

[stanfortyman]

I also agree with HK, although in the average home there is no reason to use #12 on a 15A breaker. Juts use a 20.

[abcsalem]

Thank you for your response, hkstroud.

Why a sub panel?

My main panel doesn't have any more room. I have a 100A sub-panel off
Of my 200A main, which has plenty of room.

If you use 14 gauge wire you must use 15 amp breaker. If you use 12 gauge wire you can use 20 amp breaker or 15 amp breaker. This is true whether you run one circuit or two.

I am familiar with matching wire size with breaker size. The reason I was
Planning to use 12 Gage rather than 14 Gage wire on a 15A breaker was to
Derate the circuit. The length of these wires will be on a long run, about 75-100 feet.
In the basement, there is a 25 feet 2" PVC pipe which builder installed from the
basement to the attic for running wires to attic.
This pipe already has some 10 Gage AC wire running thru it,
and some other network + coax wire in it. It's very easy to fill up a 2" pipe
With wires. Question: do I need to derate my wire/circuit for this type
Of installation? Or just put in a 20A GFCI + 12gage wire
And don't worry about derating?

Thanks in advance

[hkstroud]

Stan can correct me if I'm wrong, but I don't worry about voltage drop until the cable gets over 100 feet. You will only have 10 amps on a 15 amp circuit anyway, so you are well covered with 14 (or 12) gauge cable.

[Stratmando]

You should have separate conduit(s) for the cable/Network. Not in same conduit.
Dangerous and a code violation(s).

[abcsalem]

agreed, its safer to separate low & high voltage wires.

I have another question to run by you for the flood lights.
I am trying to install the flood lights and switches so that
two switches (in one box) on the first floor, will control two sets of outside flood lights
independently (wired through the attic). So instead of having 2 sets of romex 14/2 going from the switches to the attic then to the lights, can I bring power on a romex 14/2 wire to a double switch box and then have a romex 14/3 (black connected to switch 1,
red connected to switch 2, while = common) go up to the attic to the flood light 1,
and then run a 14/2 from there to flood light 2? This way, instead of having two 14/2
wires going from 1st floor to the attic, I run one 14/3 wire from 1st floor to the attic.

[KISS]

If your panel can accept them, you can use twins or tandem breakers as long as the # of poles for the box are not exceeded. This allows two circuits to be placed in a single space. You can get them is say 15/20, 15/15 or 20/20 sizes.

You need to get the network and coax stuff about 6" away from AC stuff and in a separate conduit if desired. This is a code violation.

[Stratmando]

Some times I like to bring 2 switch legs down from each light, This way instead of front and rear lights, you can have front, back, left and right side lights/switches.

[abcsalem]

If I understood your comment correctly, you are saying have all four sets
Of lights operate independently. During my initial planning, and initial question
I listed here, I was going to only have two sets of independent lights. One set for
The back yard, and one set for the front yard. Then after some more planning,
And thinking things through, I decided I like four independent lights.

Having four independent lights requires either four 14/2 wires, or
Two 14/3 wires. So to reduce number of wires from four to two,
I posted the question, can I use 14/3 in the configuration I would like
To install these lights.

If one is an experienced electrician, how would he install
4 sets of flood light off one 15A GFCI breaker so that
The 4 can operate independently off 2 switches in each electrical box,
And there are two electrical box, one for the back yard, and one for the front yard.

[Stratmando]

You need to get constant power to front and rear switch locations, then from switch location to corner light, then the other corner can run to switches or the first light, which ever is cheapest/easiest.
It depends on the lay out of the yard to have mabe front and left? Side be switched from the front switches, and have the 2 rear switches control back yard lights and right side of the house.
Depending on the yard, you may be better off with 3 switches at the front(Left, right, and front.
If you had motions sensors wired for front, rear, left, and right, it would narrow down the location of an intruder.