Hardwire vs. Extension Cords

[Farwell]

Glenn,
I think I read the same book that you did in reference to stranded wire having less resistance than solid for the reason you stated. I am to lazy to crack the books to confirm this but I think it is true.
If I use extension cords I like them to be at least number ten wire if I run them for any distance and plan on powering anything more than a few lights.
Farwell

 

[cwarrix]

One thing I learned when running electric to my barn the first time (yes there was a second time) is that whatever you think you need as far as power goes, double it! Guess that holds true with the size of the barn as well, should have made it bigger /forums/images/graemlins/smile.gif

Seriously, maybe you don't need double your current plans, but at least try to add in some room for extra lights and tools (a small mig welder) down the road so you don't have to redo everything.

 

[CTyler]

The surface area come into play with high frequencies, 60hz is pretty low. The stranded does not have any more resitance than a solid wire given the same circular mils. As long as it meets the rating specified its fine, were kinda splitting hairs here.

 

[bky]

I agree CTyler /forums/images/graemlins/wink.gif :cool

 

[SPIKER]

GLENN is right in this the ELECTRONS actually travel over the outer skin of the wire that means ALL of the outter skins of each individual strand of wire... this means stranded wire will carry more current than solid wire will. resistance is less as well as there is less resistance to the flow of current unless the wire has been stressed and streched alot... a GOOD extension cord will atualy heat less than solid of the same size gauge for this simple fact.


the cords will work fine for now but will break down pretty fast if too much water gets near and or in them... there are some boxes made to house outside joints like this that are water proof and the cord ends slip in and a cover closes around the joint keeps it securly attached as well as dry!

BUT out in the weather if there is any jacket problems (cuts cracks & such) the stranded will soak up the water into the strands and cause problems. like others said you need to make sure the connection in the middle remains free from water... tape will work if the ends are all good, there is actually self sealing tape too that is better. it needs an over wrap of regular tape though.


hope this helps

mark

 

[VA_Joe]

Eddie makes a good point. The easy way to get around that "permanent structure" problem is to run underground power within 5 or ten feet of the building by using a 30 or 50 amp 220 volt outdoor outlet box mounted on a 6 x 6 post.

Although I think it is dumb to have to do these types of things since they are inherently more dangerous than a permanent installation (which would also have its own building ground) I can understand how misguided zoning regs and property tax policies can make it a necessity.

Joe