[mitchell2345]

Hi,

I just bought a home and am redoing a lot of the electrical. The overall goal is to make the upstairs room a home theater. After mapping out the circuits I discovered 4 rooms were on one 20A cirucuit. 2 bedrooms, upstairs, attic, garage. over all about 25 plugs or lights.

This is way to much for this circuit. I new I had an issue when the garage opener would cause dimming lights all over the house.

I started working and ran a new 15A on 14-2 to the garage. I have a deep freeze and power tools that will pull alot of amps so i wanted its own.

I than ran a new line and moved the upstairs on its own 15a breaker. I wired it in 14-2 as well. Its what i had.

This is really bad planning but after its done I started adding up my power usage.

Here is what im guessing:
projector 3 htpc
0.666667 reciever
5 sub 1.25 blu ray
0.166667 lights 2

total 12.08333

I also have a few other small devices, switches, chargers etc. I came up with the Amps by either reading it on the device or deviding the watts by 120. The is also a couple other lights on that circuit but they shouldnt be on at the same time as the theater.

This is where i am nervous. I am coming close to 15A. Should i run another line to the room? I am not so worried about popping the breaker but more along the lines of dipping voltage on the projector. It has a $350 bulb in it and i dont want to have fluctuating voltage in it.

My thought was to run a new 14-2 to the AV rack which would take about 7A off the circuit.

Am i over concerned? should i do run a new one? I know the AMPs are all guess work and they fluctuate up and down.

Thanks,
Mitchell

 

[ScottR]

Short answer: Yes.

If your home theater system draws about 12A then you're pushing it with a circuit rated for 15A.

When you're planning loads, you need to take into account continuous loads and non-continuous loads. The short story is that non-continuous loads are those that are on for less than 3 hours at a time. Continuous is > 3 hours.

It might be a grey area, but IMO the home theater stuff should be considered a continuous load -- I know I use my setup for waay more than 3 hours at a clip.

You have to multiply your continuous load by 1.25 to determine the required circuit capacity. So if your HT system draws 12A, you would need to plan a 15A circuit for it alone. Your lighting and anything else would put you over the limit.

IMO regardless of code it's a good idea -- if someone turns on a vacuum upstairs when your gear is on then you'll pop the circuit.

In your shoes I'd run another dedicated 20A circuit for your HT equipment. That'll give you some room to add a PS3 or anything else in the future. :yes:

Use the 15A circuit you have now for lighting and misc. receptacles.

Also (again this is just IMO :whistling2 you should run 12-2 whenever you're running a new receptacle circuit. It's not that much more expensive, and it gives you a lot more overhead for future planning.

 

[Magnettica]

YES, new circuit.

 

[ScottR]

My thought was to run a new 14-2 to the AV rack which would take about 7A off the circuit.

Sorry, just re-read. Didn't realize you had lighting in your 12A total and your projector is not powered from the same location as your equip. rack. :jester:

My advice still stands; new 20A circuit for HT equipment; put the projector on it too if you can.

BTW - Generally A/V people recommend a separate circuit for reduced noise on the line, so it def. can't hurt.

 

[RegeSullivan]

Since you are doing the work anyway why not run two 15A circuits for your AV/HT equipment and make one a dedicated ground. If you ever have a problem with audio "equipment hum" the dedicated ground may take care of it but it must be done properly. As you add to your equipment you will need more power.

Rege

 

[mitchell2345]

ok thanks for the reply.

While I would like to run a new 20A to the room it will be much easier to tap into another 15A that is right below. I will put the rack of AV and the PJ on it. This circuit only has 1 plug on it. I can get to the top of the wall so i will need to drop the cable down and somehow get it in the box.

Any tips on how to do this without cutting the drywall up?

now i have learned my lesson. dont use 14-2. I was just grabbed it off the large pallet at HD not planning it out.

Thanks,
Mitchell