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lil_TXRanch
Sep 18, 2010, 03:09 PM
Admittedly long post….thank you for taking time out of your day to read/respond, it is greatly appreciated.:)

So I finally got a steel building workshop put up (30x40x12), the utility to come out and drop a pole, and now it’s time to wire it up. I have spent the last year trolling electrical forums all over the net, asking questions, reading numerous articles, and while I’m no electrician I feel this is a task I can undertake. Just looking for some feedback on my plan, cost-savings ideas, etc. Please let me know if you see any issues, safety or otherwise.

From the meter/main disconnect (200 amp), 2/0-2/0-2/0-6 copper to a 200 amp load center inside building, 55-60 feet, in 2” PVC conduit.

EMT conduit run throughout, along steel purlins, and grounded. Three branch circuits (1 for each wall, excluding front) will be fed by a 20 amp GFCI breaker. Each branch circuit will have a quad box every 5 feet.

Four 240 volt receptacles will be run, one on each major support member, plus one in a corner for the compressor that will he housed outside the building in a shed. I thought for ease of installation and future stuff that I would just make all of these 50 amp receptacles and run them accordingly; i.e. 6 gauge wire and individual breakers for each.

Lighting will be T8 fluorescents overhead hung at 11’. There will be 12-18 fixtures on three different switches and breakers. This is more for convenience and sectioning off the lighting so I’m not worried about the load on the 15 amp GFCI breaker. Depending on the exact fixture, these will either be hardwired in or plugged into receptacles (my preference).

***THHN for all wire***

Overall I’m comfortable with the load calcs, placement, etc. Just looking for some last minute feedback from those who are much smarter then I. Thanks again in advance!

tkrussell
Sep 19, 2010, 05:27 AM
The 200 amp feeder needs to be 3- # 3/0 copper with the #6 equipment ground.

#2/0 is only allowed for a residential 200 amp service entrance.

Lighting does not require GFI protection. You may if you like, but I don't recommend it.

Not sure how many quads you plan to have on each of the three receptacle circuits.

When installing receptacles on a non-residential branch circuit, for calculation purposes each duplex is allowed 180 VA (AC watts), therefore each branch circuit shall not have more than 13 receptacles, assuming none will be used for more than 3 hours.

In general, your general plan and description, is, generally OK.