Pole building electrical question

[Chilly807]

I'm with Eddie, conduit or at least BX cable is likely to be the only allowable method anyway. Check with the local building inspector, you DID get a building permit, right??

Chilly

 

[eepete]

+ 1. I agree with Eddie. At a buck a stick (10' section), and with the sections having bell ends (i.e. you can connect pieces without couplers) conduit is cheap and easy. The wire is protected, the chance of fire goes down. And if the outside of the building is struck by lightning, there's a smaller chance that your houses AC power system will be the "ground" for the strike. Smaller still if you ground the building's shell.

I took a piece of the 3/4 conduit and hi-pot tested it. I can only go up to 7500 volts, but it was happy. Romex is good to about 1200 volts, which kinda makes sense- 600 on the inside, 600 for the outside and paper. I didn't test it to a fault, just tested it to 1200. So between the conduit and the romex, you've got 8700 volts of insulation. Probably higher, that's all I tested to and that's enough for me. All the usual disclaimers here- you milage may vary, any statement about lightning is subject to being disproved by mother nature, etc. But mechanical safety, fire safety, and much better voltage insulation are good stuff.

BTW, this is also why I put conduit in any ground run vs. just using the UF (direct burial cable). Put that about 2.5 feet deep and it's quite protected, you can add more stuff later (always use bigger conduit, I'd say at least 1.5"), and the lightning strike has to be really close to where the conduit is buried to have that much kick that far down. The OP was worried about wiring in the building, but the power has to get there somehow. Also consider running some drain pipe or black polyethylene (PE) pipe for low voltage stuff (telephone and alarms).

Pete

 

[hr3]

Check with your local code office when you take out your electrical permit.. Take the picture with you.. These are the people you have to satisfy and tell you what wireing method is allowed in your area..

Building Codes Department
Courthouse
234 W. Baraga Avenue
Marquette, Michigan 49855
(906) 225-8180
fax: 225-8203
(800) 562-9788 toll free for "906" area code only

 

[firefighter jim]

You have a nice building in which you just invested a good deal of money in. Romex in an exposed building looks terrible and plastic electrical conduit above ground doesn't look much better. Go with metal EMT conduit and stranded THHN conductors. It is more labor intensive but you will end up with a professional looking job more in keeping with that beautiful building of yours. Jim

 

[JB4310]

The way I've seen buildings like that is the wires are run up overhead out of the panel not in pipe overhead but put in pipe as it comes down the wall, just straight drops down to the outlet and switch boxes. Not much run horizontally.

I prefer metal EMT over plastic only because it's easier for me, every time I have a little job I think would be good for plastic, I struggle with it.

 

[kenstrac]

I have had all types in my barns, EMT rust in some barn atmospheres using regular boxes the seal is not good enough to keep out mud wasp and you end up with corrosion in the boxes and switch and outlet failures, and the same holds true for standard Romex and BX installation's.
I have changed all of the above to plastic conduit with the appropriate plastic boxes and have had no more problems ,the only thing I have to add that if you have some long runs to use an expansion sleeve so you won't have the conduit bowing from heat expansion.

 

[EddieWalker]

While I agree that nothing says professional electrician like metal conduit all run perfectly, with nice, sweeping turns all lined up. It's not an easy task to accomplish, and if you don't know what you are doing with metal pipe, it's real easy to make a real mess of it.

Plastic Conduit allows amatures to do the job with good looking results. The key is to make sure your runs are straight and level.

Eddie

 

[Stampeder]

I too agree with Eddie. I am currently adding wiring to my barn which was done by an electrician previous to my owning it. I am using plastic. It is a dream to use. I have EMT benders etc. but gluing plastic is way easier.

BTW don't run horizontally along the walls. If you later want to cut a door or window etc into the wall it's a royal pita, trust me on this one.
Make your runs down the center of the building along the rafters then branch off to the walls and vertically down the walls where you need boxes. Besides any lights will be up there anyway.

Hope this helps and good luck.

Glenn.

 

[Iplayfarmer]

...Also consider running some drain pipe or black polyethylene (PE) pipe for low voltage stuff (telephone and alarms).

Pete

Educate me here... Why not just make another run of conduit?

 

[smfcpacfp]

How do you stop the electricty from freezing up in the wires up there? Do you have to insulate them?
Perhaps some steam tracing like we use in the plant to keep the pipes from freezing??

Electricity conducts best near absolute zero, so in the winter here, all electric appliances run better, the lights are brighter, etc. .