View Full Version : Electrical runs for the equipment, 20 Amp, 15 Amp, nothing?


scorpion
12-21-06, 06:01 PM
I am doing a retrofit structured wire pull (long story, but the telephone lines are problematic, we already ran the coax for satellite, so running to a new location is a joke, and my walls interfere with Wifi), and putting all my AV equipment in there as well.

My question is, while I am cutting wholes in ceilings and running through the attic, should I bring more power to that location? It currently has a regular 15 Amp receptacle, and doesn't really share much). Here is my decision:

Run a dedicated 15 Amp or 20 Amp circuit, run two dedicated 15 Amp or 20 Amp circuits, do nothing and just add a few more recepticals on the existing circuit to keep things clean.

Here are my thoughts:
If I run a new circuit, run 2. The incremental cost of 14/3 or 12/3 wire over 14/2 or 12/2 is next to nothing, and its only a few extra bucks for a double circuit. Having two circuits would let me put things like dual-power supplied servers (happen to have one) onto both circuits, so if one flips, so what. It also lets me distribute the load between them to keep from blowing a circuit.

20 Amp vs 15 Amp, the reason for 20 Amp is that its more power, 12/3 isn't that much more than 14/3 wire, and it has that "commercial gear ready" feel. The draw back is that I am putting tamper-proof outlets all over the house (my son is probably going to crawl soon), and the 20 Amp outlets wouldn't be the same tamper-proof as everywhere else.

Will I regret not pulling the power? It is an unpleasant run, I have to do it over the flat roof, and will cost about $200 (new work boxes, receptacles, wire) for 15 Amps, $250 for 20 Amps. We already had to patch part of that ceiling from a leak, so repainting is in the works anyway. Now is the time for the run... and if it goes well, I might even rewire my screwy light-fixture/fan mess right now instead of just using Insteon to get it all sane.

Will I take advantage of having more power in the closet? It will keep any servers, AV equipment, security systems, etc., that I add to the house.

Thanks for the advice,
Alex

AV Doogie
12-22-06, 04:22 PM
As Tim the Toolman says "More Power'. I would extend the service to include at least two 15A outlets if not two 20A outlets. As we go into the future, more electrical products using more energy are becoming a norm. Can't hurt?

scorpion
12-24-06, 05:10 PM
Definitely of the "more power" school. I'm leaning towards the 15 Amp option, not for any technical reasons, but just to be consistent, the rest of the outlets are 15 Amps, with 20 Amp circuits for special purposes. It also seems that all gear designed for the home is based upon 15 Amp circuits. My circuit box is getting a bit filled, and I'm going to avoid the expense of a permitted fork lift to a more modern circuit breaker for now.

The dual circuits seems like a no brainer. My main reason also is to have clean power coming to the equipment. Having a dedicated circuit means one place to filter, one place to clean, etc., and keeping all the stereo gear on one circuit and all the computer gear on the other seems like, from an audio point of view, cleaner...

I also figure that eventually I'll be able to get a UPS or two with redundant power supplies, which would let me put it on both circuits in case one flips.

takeaim
12-24-06, 11:11 PM
I ran 80 amps from the main house panel (400 amps) to a sub-panel in the equipment room at the back of the dedicated HT. The 80 amp panel has a surge protector. From the 80 amp panel is 4 20-amp receptacles. Each receptacle feeds a quality surge-protected strip. Equipment is plugged into the strip, such as

Strip 1. Low power devices that don't draw much; DVD, VCR, Panny projector, cable box, etc. Sine wave back-up power supply of 14 amps keeps everything running smoothly. I don't want power surges possibly negatively affecting the equipment. Also a Richard Gray power conditioner.
2. Buttkicker amplifier
3. Receiver (soon a pre/pro)
4. Future separate 7-channel big amplifiers

The subwoofer is on its own 20 amp dedicated circuit in the front of the HT.

As long as you're running wire, run a lot. It's cheaper to really do it up right the first time. Who knows what electrical requirements you need in the future. Overkill? Why not, it's my HT.
Take Aim

Daverph
12-25-06, 12:55 PM
I ran a dedicated 20amp circuit for the equipment and a dedicated 20amp circuit for my projector (hopefully to eliminate any interference issues). If the equipment ever needed more power I can always tap the dedicated projector circuit because I was dubious to the benefits of only having the projector on a dedicated circuit.

miltimj
12-27-06, 03:38 PM
I'm curious about your mentioning of 14/3 and 12/3 versus 14/2 and 12/2.. What does that have to do with running multiple circuits? 3-conductor (not incl. copper ground) are used for 3-way (and up) switches, etc. You don't run multiple circuits off a single wire.

I agree that two 20amps are necessary, and even more if possible. 1000 ft of 12/2 is something like $80.

scorpion
12-27-06, 05:36 PM
According the Wiring 1-2-3 Second Edition, the current trend in kitchens is to run dual circuits (or GFCI and single circuit, depending on local zoning). Basically, using a 14/3 (or 12/3 wire), you carry the neutral and ground to each receptical, and you run one circuit on the black wire, and one on the red. You either run the black on top receptical and red on bottom, or you could do every other receptical.

You believe that 20 Amp is more useful than 15 Amp, and dual runs make more sense than a single run. Is there really an advantage to 20 Amps? I was also wondering if I had 2 or more outlets on each circuit, if I could use 15 Amp rated tamper-proof outlets, but have 2-3 of them, on a 20 Amp circuit. I really was hoping to keep my tamper-proof outlets. I was also considering running the 12 Gauge wire, but putting 15 Amp circuit breakers and recepticals in, because then upgrading the power by 33% is really easy.

Alex

miltimj
12-28-06, 06:36 AM
Are you absolutely sure it says to run two completely different circuits off of one 12/3 or 14/3 wire? Meaning, you connect the red to one breaker and the black to another? There's no way that's the case, because they would use a common ground and result in pushing 30 or 40 amps (15A vs 20A breakers) through the white neutral wire.

You mentioned running one outlet on one and another outlet on the other wire. That's commonly used for a scenario where one of them is switched and the other is not, but you must break the metal tab on the side connecting the two outlets.

The reason to use 20A is if you ever want to have more than 12A or so on a given circuit. If you think you will, then err on the side of 20A. Standard now is in kitchens, bathrooms, workshops, laundry rooms (not incl. electric dryer), and outdoor. Note that there are 20A outlets that don't have the horizontal plug type. They're a bit harder to find, but they exist and work very well. Those are the only ones I use for 20A circuits. So your safety covers will work just fine (or are you talking about a special outlet that has some cover over it? I'm assuming you mean the plastic covers you plug in).

Regarding the number of outlets per circuit, it really doesn't matter. It depends on how many outlets will be used concurrently. Typical might be the outlets in a few bedrooms near each other, and one for outlets in the main area. That may end up being 10+ outlets. The limiting factor is the power going through them, not the number of "taps" (outlets) into the power.

It's not really advisable to use 12 AWG wire and a 15A circuit breaker and outlets. I'm not sure it's even up to code, though IIRC it is - you just have to have the same AWG wire for the entire circuit (and obviously meet the amperage requirement). Note that I'm not an electrician so take this advice at your own risk, but I have done pretty much everything electrical from a breaker panel in. Also, all of this will depend possibly on amended code requirements at the local level.

miltimj
12-28-06, 06:51 AM
You got my curiosity up, so I did a bit more research on this, and found this article (link (http://www.inspect-ny.com/electric/multiwir.htm)).

Using a double-pole breaker assures that the two legs of the circuit will be forced (in most panels) to opposite legs of the 240-volt panel - a requirement when circuits use a shared neutral, such as in multiwire branch circuits. If individual 120V breakers are used, it's possible for a future modification or rearrangement of breakers in the panel to in advertently move one or both individual breakers so that they both end up on the same 120V leg of the panel - which is improper when a shared neutral is involved. (Improper because the shared unbalanced load could exceed the rating of the wire.)

So it seems that it's possible, but you need to ensure the breakers end up on different phases of the panel. It'd still be my preference to use two 12/2 wires, but I can also see the convenience of running a single 12/3, especially if the run to the breaker panel is long or difficult.

scorpion
12-28-06, 11:52 AM
Thanks for the link. It's a long and difficult run, and running two 12/2 wires will be much more difficult (larger holes through studs, etc. Using a bonded breaker seems like a reasonable approach. That way, they are "effectively" one circuit for safety (cut one cuts both), but you are running 40 Amps of power split between the recepticals. That would give me sufficient power with a single run, an only add about $10 to the circuit breaker costs.

I am not an electrician either, and if I have my electrician do the run, I'm going to spend a fortune (and he makes a mess of the sheet rock). However, I think that having the extra power in the wiring closet is probably worth doing the run.

scorpion
01-03-07, 11:31 PM
Thanks for the ideas guys. I appreciate the sub-panel idea, and agree that it's the "right"solution for a dedicated HT, but not for my house. It's a really challenging run, so running 2 12/2 wires is out. It seems like the consensus is that 20 Amp is much more useful than 15 Amp, and other than needing to use the plastic safety plugs instead of my tamper-proof outlets, isn't a problem.

The dual-circuit breaker is ironically much more expensive (much being $20 vs. $6 or $7) than the dual-switch without the "bonded switches" which is kind of funny given that it isn't any more difficult.

Thanks for the feedback from everyone here.

video_bit_bucket
01-04-07, 02:45 AM
One reason for using 20 amp circuits is that the sustained load (by code as I understand it) is not supposed to exceed 80% of the max circuit rating. So a 15 amp circuit is only good for 12 amps, 1440 watts at 120V sustained load. Yes HT audio loads are transitive but video tends to be less so, plasma excepted. The APC HT15 is showing 6.5 amps, subwoofer goes around the APC, this is just watching TV at low volume right now.

miltimj
01-04-07, 03:38 PM
Your plasma and receiver draws 6.5A?!? Wow, that's insane. I'd feel like I was being robbed every time I turned on the TV. I suppose it's like bulb life in a PJ though... you essentially have a pay per hour usage rate, though that's only about a nickle an hour based on rough calculations in my head... (So I guess this post was just thinking out loud.. :) )

video_bit_bucket
01-06-07, 12:09 AM
But I don't have to run the heat much in the winter. :)

JohnG316
05-23-08, 08:55 AM
Thanks for this thread!

I was just trying to decide whether to run two 15A circuits or two 20A circuits to my equipment closet. The wiring run is no real issue for me, and thanks to this thread I think that 20A is the way to go with two 12 GA wire runs.

I'll have one circuit primarily for subs (I have 4), and the other will be for everything else (receiver, DVD player, projector, etc).

Maybe this way I can actually pop popcorn in the microwave, make coffee, and watch a movie all at the same time without tripping the basement circuits. LOL.

Does anyone know whether it's within code to run the wires parallel through the same stud holes? I believe this will be OK, but I just wanted to check and see if anyone suspects otherwise....

Thanks!

John

miltimj
05-23-08, 10:42 AM
I'd definitely run two 20As as you said, John. And additional ones for the microwave/coffee pot/etc.

You can run wires through the same holes - there becomes a limitation of wires in the junction box based on their size. That said, avoid low voltage and high voltage together (as you probably know).

JohnG316
05-23-08, 01:25 PM
Thanks, Tim!

Yes, the non-theater stuff (coffee pot, fridge for drinks, microwave) will run off the existing 15A circuit already set up with receptacles in the basement.

Many thanks for the reply!

John

Karp
05-24-08, 08:54 AM
You can also use 15A outlets on a 20A line if you choose to. Just never run 20A outlets on a 15A line! 15A outlets are rated for 20A pass-through.

I ran two 20A lines - One for my equipment and sub and one for my projector, lights and convenience outlets. My outlets are all 20A

tleavit
05-24-08, 01:38 PM
Running extra power was one of the best things I did in the HT.

I ran a 2nd 60 amp panels to the basement. 2 dedicated 20 amp circuits and 1 20 amp circuit to wall heaters. That alone with 2 more dedicated 15 amp circuits have given my theater all the power it needs with lots of room for growth. I've not had one power issue at all. While the 7 200W Outlaw monoblocks aren’t the worst amps out there for power, they still need the love.

http://www.silverti.com/ht/Theater%20July%2014,%202007/DSC06249a.JPG