# 2 Part Electrical question...

• posted on January 3, 2011, 9:36 pm
This is a long post but I'm young and dumb and you guys are smarter and I'm bouncing ideas off.
I'm converting the reading room in our home into an office. Against one wall I'd like to build and install a built-in that has two desks with a bookcase in the middle. Both desks will house computer workstations ie printers and monitors etc. Since they are work areas I'd like two lights above the desks and for effect, lights along on top of the built in.
First off for the computers, can I use a split receptacle (15 amp) without issues to power both desks? I'd like the outlet in the bottom of the bookcase (exact middle of the room) because it'll house the router and modem and back-up drives etc. Run one power bar that powers one computer and all of it's peripherals and use the other receptacle to power the other computer and it's peripherals. The router amd modem and such will have to share with one of the top or bottom of the split.
Is this a split receptacle idea dumb idea or overkill? Or should each work station get it's own outlet and keep one outlet in the middle of the bookcase and have all three outlets on a single circuit or on two circuits? Should I look at 20 amps if a single circuit?
Second off all I'd run a new line for all the lights plus a new line for the computers. So that's two wires I gotta snake. Problem is the wall with the built-ins is 60 feet (straight) from my panel box. Figures eh. The room sits on a concrete pad so I can't run the electrical wire underneath the floor. The only accessible path I can run the wire where I have 60 feet of access to snake it the length of my house has both an air-return and an 8 x 16 x duct work in the way.
The duct is actually directly below the air return pathway running parallel to it. The air return pathway is just sheet metal nailed to floor joists so I'm thinking I can drill thru the joists and snake my wire thru the air return. I saw this idea at my cousins 80 year house they just bought 2 months ago. My uncle and I laughed when we saw the electrical wire snaked thru the air return and it was resting on metal. I might not be laughing anymore. Mine won't touch metal but it'll go thru a return air pathway. Again dumb idea or not?
Thanks for hearing me out!
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<%-name%>
• posted on January 3, 2011, 10:39 pm

*For a home office I would install double duplex receptacles (Two gang box) above and below each desk. One 20 amp circuit should suffice. Install another double duplex where the router will be located.
Install a couple of recessed lights above the desks with a switch for each desk. Install a third switch that controls a wire that comes out above the built-ins. You can hardwire some lights or attach a receptacle and plug some in.
You cannot run Romex cable through a plenum. You would have to use conduit. I have had some luck fishing cables through the box around ducts using fiberglass rods. Takes a little patience and it is good to have a helper.
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<%-name%>
• posted on January 3, 2011, 10:51 pm

Tis a long one. If I miss something and no one else catches it, ask a follow-up.
We have 2 computers with 600 watt PS and a laser printer all working on one circuit. I have never checked to see if it is 15 or 20 amp. It has other stuff on the same circuit. It is just the wiring that came with the house. One of these days I might pull a new wire because there is a momentary flicker of the light when the printer powers up. Two computer on one circuit would be fine. No where near load. I would install two duplex outlets because you can never have to many plugs.
I don't know the modern code but feel fairly sure that romex in a return air is not allowed. That said, I have a couple of houses where there is some and there have been no problems over many years. If I were going to install it that way, I believe I would use conduit just to cover my butt. I would not run it through the supply side at all. There has to be a path you can take. Wire is flexible and a few extra feet costs very little.
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Colbyt
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<%-name%>
• posted on January 3, 2011, 11:29 pm
In typed:

Sounds like an interesting plan. My 2 cents:
4 ckt breakers for ideal situation; mod as required:
- One duplex for each computer. - Each computer on a different breaker for separation. - One duplex or more as wished for the printer/s. - Preferably on their own breaker or at least not shared with any electronic equipment. Laser printers like to pull a lot of power to keep the fuse up to temperature. But, could be shared with lights, etc. as long as the momentary blinks don't bug you. Better on its own ckt though; check printer specs for size of breaker needed. - One duplex for the rest; lights, etc..
Duplex outlets, if so wanted, have a bar that can be cut, enabling each outlet in the duplex to be from a different ckt breaker.
Missing: UPS. They're cheap enough, one of each computer/monitor if feasible. Often cheaper than one large one.
That would make pretty much a dream setup with minimal problems foreseeable except of course, Security software for each machine.
You could also connect one computer through the other for i'net connections and get away from needing two connections. A small LAN like that is easy to set up.
Good luck!
Twayne`
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<%-name%>
• posted on January 4, 2011, 10:11 am

What is on the other side of the wall? Is it a bedroom with its own circuit? If so, maybe you can take a couple outlets off that circuit since bedrooms don't take many amps. Also, what's on the other wall. What's there already? If you can use other circuits, it may be a real easy job. Don't over-think it.
Hank
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<%-name%>
• posted on January 4, 2011, 12:16 pm

What is on the other side of the wall? Is it a bedroom with its own circuit? If so, maybe you can take a couple outlets off that circuit since bedrooms don't take many amps. Also, what's on the other wall. What's there already? If you can use other circuits, it may be a real easy job. Don't over-think it.
Hank
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Another long long response. Don't get mad at me guys :)
There is a picture link at the bottom showing my air return.
My house is a 60 x 28 foot side split bungalow, developer built in 1968. one storey on on side, two storey on the other side. The room I want to do this work is in the two storey part.
The wall I want to upgrade the outlets and lights is against the garage. I want to garage to keep its own circuit for electric heat and use of 15 amp motor power tools and electric lawnmowers. Another wall of this room is also against the front exterior and a third wall against a hallway. It is this hallway that I have easy access to snake wire because it is a drop down ceiling.
Currently the room has three circuits, all tied to other areas of the house. One outlet is on a circuit that powers all the outdoor light fixtures (6 fixtures with all the related travel switches) plus a bathroom light and outlet and vent fan plus 2 separate basement light fixtures. Right now this outlet is also powering a small flat panel teevee, and one computer workstation. I will keep this outlet to power a television and gaming system and dvd and all that jazz.
There is another outlet on the opposite side side this room that is tied into a main living room circuit. This same circuit in the living room has a 1000 Watt electric fireplace using it. The third lights up two wall fixtures. This circuit also powers all the hall and foyer lights and chandeliers and living room lamps. Above the room are three bedrooms and the master bathroom. Two bedrooms and the bathroom are all on one circuit. The last bedroom is on a different circuit but I cannot find the wire to powers it.
The easiest way to power the electronics I think is it's own circuit. I have plenty of room in my brand new panel box and it's easy to snake new wire across the length of my house. It's actually easier to do new than to starting busting holes in drywall looking to tie into underused existing.
The only problem if laying a new wire (s) is this bridge: http://www.flickr.com/photos/henchman171/5323066103/ The air return supply is just nailed sheet metal. About 1/2" below is the furnace/a/c supply. I wanted to drill a hole in the two floor joists that are part of the air return and pass new wire thru that to get to the other side.
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<%-name%>
• posted on January 4, 2011, 1:49 pm

*According to Article 300.22(C) exception, you are allowed to do that. 300.22(B) specifies MC cable for use in environmental air as well as metal conduit including Greenfield. 300.22(C)(1) also specifies MC cable or metal conduit.
Use MC cable with a metal sheath, but not PVC coated and you should be fine.
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<%-name%>
• posted on January 4, 2011, 12:54 pm

You can't run wire in duct work. Is this a single story house with the duct work between the two floors? Or is your attic space really that small? If you really want to run more wire then run it through the attic and down. If this is a 2 story house plus 60 ft from the box you may want to run 12 instead of 14.
Frankly the existing wiring should be able to support what you want. The typical computer is just a hundred watts or so. Try to buy energy star and it will be even less. If the room already has a ceiling light fixture you can run from that to add more lights.
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<%-name%>
• posted on January 4, 2011, 5:34 pm
On 1/4/2011 6:54 AM, jamesgangnc wrote:

No way, unless it's ancient, or a laptop. Times two (two computers). Plus you've got all the peripherals to power, too. You know - two monitors, at least one printer, modem/router, sound system, and whatever else the OP may be using.
My brother and I were looking at an eight-thousand dollar custom built gaming rig. That sucker pulled a lot of watts, mainly due to the dual high-end graphics cards and sound system. I told him for that price, they should throw in weekly pizza and stripper deliveries for the first year.
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<%-name%>
• posted on January 4, 2011, 6:47 pm

He's using them for business. Not high end gaming. Most mid range computers have a power supply that max's out at 2 or 3 hundred watts. They seldom get close to that in actual usage. Often less than a 100 watts. Lcd monitors use way less power than the old crt's did. Some under 50 watts. You'd share one printer between the two computers and it would probably be asleep 99% of the time. Add a few wall warts for routers, etc.