Electrical Outlets in Basement HT (1 Viewer)

[GrahamO]

I am having my basement done in a couple of weeks and will have a dedicated HT. The total basement will have three large rooms and we have four breakers that remain open on the main in the house. The contractor plans to use three: one breaker for each room and leave one open "just in case for down the road."

My question is whether I will regret having all my HT equipment on the same room circuit as the lights. Some forums have talked about having a "home run" to the outlet you plug all your equipment into. This supposedly decreases interference and stabilizes the load. While I do not think my equipment is extremely power hungry, I want to make sure I do it right upon construction. The power hogs will probably be my Denon 3802 and Samson 1000 with the SVS 20-39+ (coming soon).

Anyone with some elctrical insight? Should I use the last open breaker for my equipment outlet? My mechanical engineering degree is not doing me much good right about now! Thanks.

Graham

 

[Dave Gates]

Welcome to the HTF Graham.

When I was planing my basement Home Theater project, the wiring (power, speaker, video, voice, data, sub) was the part of the project that I had the most questions about. And my ME degree didn't help me much in this area either.

However, what I found out, was that for the best possible performance of your system, you should have a dedicated circuit for your equipment. Not only for equipment power requirements, but also for line interference from lights and other sources. And now is the time to reduce, or eliminate any potential signal degredation problems.

So to answer your question, yes, I think you would regret having your equipment on the same circuit as the lights. Especially if you have interference problems down the road. It is cheaper to pay for the extra wire now when the walls are being built, than try and pull a dedicated circuit within a finished room.

Good Luck!

 

[Bill Kane]

Graham,

As Dave notes, NOW is your chance to get HT wired up with a dedicated circuit -- I presume 20amp? By the same token, have you consider TWO dedicated circuits? Not particularly overkill parts costwise.

What if you succumb to separates upgrade? Or two subs? I just added an 1800VA 200Wx5 amp to my existing living room 20amp circuit that also controls the master bedroom lights on the other side of the wall and two incandescent floor lamps in the living room. Luckily, the circuit is holding.

But even turning on the tv, the floor lights flicker a bit. I dont worry, but if ALL my HT gear was running at MAX power, theoretically I certainly would exceed the recommended 1950-watt safety limit for 20amps (2400 watt max I think).

Two HT circuits certainly would remove any lingering power-limiting concerns, I should think.

 

[Wayne A. Pflughaupt]

Graham,

A dedicated outlet “by nature” would be a home run from the breaker panel. However, it is fine to install all the outlets you need and where you need them for your equipment.

For instance, if you plan to have a sub several feet from the equipment, go ahead and drop an outlet next to it. This will make for a cleaner installation – no cables strung across the floor. (Drop a signal cable there, too, while you’re at it.)

Of the other hand, there are practical benefits to having a home run for each outlet. It would allow you assign any outlet to any circuit at the breaker panel. That would insure your installation is future proof – power-wise, anyway.

Regards,

Wayne A. Pflughaupt

 

[Kerry Hackney]

Graham, It is possible that you have more than 4 spaces available. Depending on which panel you have, it is possible in a lot of cases to use "half size" breakers and gain more circuits. If you look on the inside cover of your panel ,the mfg part number will tell you the maximum number of circuits available. Your electrician should be able to tell you as well. FWIW, I would definately run one or even two dedicated 20 amp recepticles to the equipment. It won't cost that much more. If the room is large, I would have the lighting on one circuit and the plugs on another. A side benefit is that you don't have to work in a dark room if you have to turn off the breaker for some reason. Code is one recepticle every 12' around the room. That way, it is never more than 6' to a plug.

 

[SanfordL]

Hey, one other thing to note is, if you are going to have dimmers in your HT basement, they are going to throw so much garbage into the lines, and you will hear that distortion, that it will drive you bAtTy. At least it did me....
That having been said, and not knowing what kind of lighting you will be running (florescents [sp?] can add humm I hear) the idea of a circuit per outlet seems like a bit of over kill unless you have enough space in the box, or want to run an auxillary box - which might be a good idea anyways. If your main service can handle it, get a little Square D box from Home Repot, Menards, Lowes, etc. and evaluate the load you'll be running. I would leave the lights on your main box on the 15 or 20 amp circuit they are on now. The deal would be to run the aux-box down to your HT basement, then you have all the breakers right there. I assume you are going to have some of this equipment in a ventilated closet so you don't listen to the hum of that sub fan all day long so just slap the box in there.
Anyways, just throw a 60 amp circuit (if you need more than that, then don't ask me because that sounds like a huge service upgrade) into your main box to run the aux-box, and then run the conduit into your basement and start wiring. If my memory serves me, a 60 amp aux-box will handle up to 4x20 amp circuits (figuring 80% load factor per circuit) and that should be adequate. Of course, I am not an electrician, but you should evaluate your main box's load right now, and if it can handle the onus of the additional load that could be drawn.
You might consider sending Gary Silverman an email, as he is the resident electrician and will tell it to you straight. Just check out this thread http://www.hometheaterforum.com/htfo...threadid=36527 for his info. Note, Gary, if I said anything wrong, don't worry about correcting me, otherwise how do we learn, without burning our house down.

 

[Paul_C]

I agree with the replies already posted. I have few comments worth about 2 pennies.

1) If you go with 2 20 amp circuits then make sure they are on the same leg of the panel. This will minimize crosstalk between the two circuits.

2) Try and get the electrical runs as low as possible in the wall so that they will not interfere with low voltage cabling such as speaker wire. My designer suggested that I ask the framer to notch the bottom of each stud before nailing so that a channel is already there for the electrician. It would also save the electrician time and effort because he/she wouldn't have to do any drilling.

3) If you are tight on breakers then do yourself a favor and get a 30 amp circuit. You will want a front projector one day and the upgrades on those 7 channels of glorious sound will eat up a 20 amp circuit very fast.

Paul.

 

[tony randall]

Whoaaaaaaaa. First, get the amp data from all your equipment and add it up, and make sure you have enough amps on the circuit for the HT equipment.

I am not clear if you are running this all from your main panel or not, but you would be very wise to run a sub panel from your main.

If you run the sub-panel, check if you have 200 amp service. If so, get a good sub panel, and put in a 240v line from the main panel to the sub; you will get better current that way. (run 110 out of the sub panel!!!)

You didnt specifically address the other electrical requirements you will need, like a popcorn machine. Then you might need a central vac system put in to clean up all the crushed popcorn on the floor...

Remember that the current being delivered can fluctuate, so you should try to deliver the current to the outlets where you plug in your HT equip as clean as possible.

 

[GrahamO]

I sincerely appreciate all the help. Let me try provide some more data and see if I have extracted the best solution.

My entire house is on one, 200 Amp main panel. There are the standard 32 breakers spaces with 27 in use. My basement design, as it exists today, will use another 3 of those (no idea the amps on each). My theater is 15' x 21' and is totally enclosed. The design has six wall sconces on one wall dimmer as well as 4 recessed lights on a separate dimmer. These are all on the same circuit as the outlets.

My equipment will be (** are items not currently in system):

Denon 3802

**Old Sony Integrated Amp to run multi-room **SVS 20-39+ with the Samson 1000 amp (coming soon)

Toshiba 2700 DVD

JVC XLM400 CD

Toshiba VCR

Toshiba 53" RPTV

GI GFT2000 Cable Box

**Panamax 1000+

B&W Speakers all around (5.0 today, 7.1 with new HT)

As a note, I also use an X-10 system to turn my Toshiba TV on/off through a Pronto macro. Toshiba does not have discrete on/off codes.

My rack will be in the back corner of the room and the TV in the front. Net, these will be on two outlets.

My current thinking is to run a sub panel with 4 20 amp outlets per the recommendation of a couple of folks. I would route this to my HT and have two dedicated outlets for my rack, one circuit for the lights and one for the other outlets in the room. Does this sound about right?

Graham

 

[Dennis Erskine]

It's WAV boys and girls. Watts = Volts x Amps. (line losses, etc not included). If you need to know the total amps divide the total watts on the circuit by the volts. Give yourself 10% margin. IE, 110 volts on a 20 amp circuit should carry no more than 1980 watts.

 

[Scott Jelsma]

Graham,

I would agree with the previous replies which recommended that you put a sub-panel in your basement. This way you know you have plenty room to put in as many breakers as you need. I would run a minimum to two 20 amp circuits dedicated for your AV equipment. Be sure your lights and any other electrical sockets are on separate circuits.

Paul_C,

You said to be sure the two 20 amp circuits are on the same leg of the panel. Can you explain a little more what you mean by this? I've heard people say something similar before, but I'm not sure exactly what you mean or the purpose. Do you mean that if you have 240 to a panel, be sure that both circuits are connected to the same 110 line? (I believe this would be every other breaker on most panels). If so, what does this accomplish for the AV system?

 

[Wayne A. Pflughaupt]

Not sure what Paul meant by :

If you go with 2 20 amp circuits then make sure they are on the same leg of the panel. This will minimize crosstalk between the two circuits.

Crosstalk is an unwanted phenomenon occurring in audio signals.

Nevertheless, Scott, you are correct that this would mean connecting both circuits to the same 110 leg. The wisdom of putting both circuits on the same leg is to minimize the chance of ground loops. This is standard practice in professional audio applications. Seems strange, since you typically have to have two or more functioning grounds to get a ground loop. However, this is the way the pro audio companies I used to work for spec’d jobs. With one of those companies the owner was an EE, so I figure he knew what he was doing.

Regards,

Wayne A. Pflughaupt

 

[SanfordL]

Hey Graham, sounds like you are on the right track. Just make certain that your aux. box has enough juice for when the upgrade bug hits, and it will. You might consider enclosing where you are going to house the Sampson amp, because I read a review somewhere about how LOUD the fan is on that amp. And, if you locate your amps towards the back of the room, away from the TV, it is probably going to be very close to your seat, and your head. Just a thought....

Do you have your HT down in the basement now? If so, do you notice any noise from the dimmers? I am curious because I have read before how much junk a dimmer throws into the line, but have not had any experience with it.

Next, Dennis, I must agree with some of the WAV deal, but remember, per the N.E.C. you can safely(!!!) only run at 80% load factors of total capacity. Hence, a 20 amp circuit should not be burdened with more than a 1760 load assuming you are only receiving 110 in. Not that the circuit can't handle up to 1920 (this is what you meant right? 120 volts x 20 = 2400 * 0.8 = 1920. If you assume you get only 110, then the math comes out to 1760 for a safe circuit, or 2200 if you are willing to run right to the edge of what the circuit can take) in small bursts, your wires and circuit will get hot running this close to the edge. Most circuits (particularly Sqare D's that I have experience with) will blow if they get too warm so unless you want to run to the box every five minutes or whenever the bass cranks, leave some room to BOOM in your circuitry.

 

[Paul_C]

Scott;

Wayne has it correct. I had it wrong (about the crosstalk issue). :b

It is more of a safer than sorry situation. Ground loop hum can be fixed after the fact but why take chances.

Good luck.

Paul.