[Coco] Powering a computer room/ham shack?
lamune at doki-doki.net
Thu Oct 1 01:19:42 EDT 2009
Hey Frank, I wouldn't recommend replacing the outlet device as described. If you have a fire in the house (even if it's totally unrelated) and the insurance adjuster sees the un-approved electrical work, you may find your claim voided. Best to be on the safe side and pay the inspection/permit fee.
> -----Original Message-----
> From: coco-bounces at maltedmedia.com [mailto:coco-
> bounces at maltedmedia.com] On Behalf Of Frank Swygert
> Sent: Wednesday, September 30, 2009 12:12 PM
> To: coco at maltedmedia.com
> Subject: Re: [Coco] Powering a computer room/ham shack?
> Running a 20A 220 circuit on 12 AWG is fine (two hots and one neutral).
> That's really all you need to worry about. Run the 20A 220 to a small
> sub panel. You'll only find 125A sub panels at Lowe's and such, but
> again, that's not a problem. I don't know how many circuits you can
> run, but as long as you don't exceed the 20A draw you're fine. Most sub
> panels are run with a 30A or higher breaker, but they are run with more
> draw in mind than what you have. I have a six breaker sub panel run in
> my house but with a 50A 220V breaker in the box. I have 5 20A and 1 15A
> breaker in the sub panel. This is just to divide lighting and zone the
> outlets. The 15A breaker is for the lights, probably no more than 1A
> draw with just over 100 watts of lights -- compact fluorescents -- and
> that's if all are on at the same time... well, cut the ceiling fan on
> and it might pull 2-3A. I don't know what the percentage over the main
> breaker for the sub panel is (in your case a 20A), but I know it's at
> st twice the amount. If you're just putting 2-3 15A breakers and 15A
> outlets in you're more than covered.
> You might want to just run 1 220V receptacle in a box with the spare
> circuit until the inspector leaves. Then replace the receptacle and box
> with a sub panel and 3-4 15A outlets, either each on their own breaker
> or a pair on each breaker. I'm not recommending you do something
> unsafe, as the 20A breaker will blow if you overload. It just makes it
> easier for you to do without explaining anything. The inspectors
> usually take the tack of "if you sell the house the new owners won't
> know and might just stick a bigger breaker in." My thought is if
> they're that stupid they're likely to screw something else up and burn
> the house down too, you can't idiot proof everything!
> Most just don't run less than 30A to a sub panel, but your idea is more
> to spread the load around, not put more than a 20A load on it. You'll
> only have a problem if you start tripping the 20A 220V breaker. No
> electric heaters down there!! Legally, you can work on your own wiring,
> just not if it is a rental or commercial space (at least in most
> #12 wire is good for 20A. http://www.electrical-
> Date: Tue, 29 Sep 2009 19:28:02 -0500
> From: "John E. Malmberg" <wb8tyw at qsl.net>
> I am trying to set up a workshop where I may be able to play with my
> COCOs and other toys again, so this is not totally off topic.
> Unfortunately the builder of my house, while putting in the plumbing
> downstairs bathroom, only put one spare power cable, a 12 AWG with 3
> insulted wires and a ground. That would be good for 2 20 A split
> neutral circuits.
> This is in addition to the required single 20 A circuit in the basement
> that is currently active. Combined that gives me a total of 60 A in
> The resulting 60 Amps is more than sufficient for powering the expected
> TVs, Ham Radios, and computers, and workbench tools.
> I would prefer though to have a sub-panel with multiple circuits, where
> each circuit would just be 15 A, for the computers and the Ham Radios
> and TVs.
> I have not been able to find a strong reference as to if this would
> a housing inspection.
> All the references on the Internet I have seen is using 30A dual
> breakers and 10 AWG feeders to a sub panel. Putting in the 10 AWG
> feeder would be difficult as there is no good path from the main panel
> in the garage to the basement. I would likely have to run visible
> conduit on the outside of the dry-wall. As such, I would probably have
> to get a professional to install that.
> The NEC does seem to have tables indicating that a 20 A feed is
> as long as 20 A ganged breakers are used to protect it.
> Frank Swygert
> Publisher, "American Motors Cars"
> Magazine (AMC)
> For all AMC enthusiasts
> (free download available!)
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> Coco at maltedmedia.com
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