Electrical questions??

IaGary · Jul 22, 2011

I am putting in a new service to power my grain bins.

I have a new 200 amp disconnect breaker box that feeds two 60 amp sub panels that are fed with #2 alumium wire from the 200 amp main. Can I add a #8 copper to feed another sub panel and tie into the same lug that the alumium is under on the 200 amp main disconnect breaker?I have room, just wondewring about mixing copper with alumium. I do have a tube of the compound to put on the wires to reduce oxidizing.

Question 2. What size copper wire is required to ground this new 200 amp panel? I have two 5/8's diameter grounds rods in the ground as to the power company's request. I am guessing #8 or larger?

Gary

Ken-Pa · Jul 22, 2011

Drive (2) 8' grd. rods at least 6' apart below ground surface so nothing can cut them off , The grd wire should be buried in a shallow trench fro rod to building wall . Connect #4 bare copper with up to code rod clamps . As for connecting copper & aluminum wire together - not a good idea even with the oxidizer grease . If you was asking about using aluminum wires for circuits , I would use only copper , Aluminum entrance cable only is safer . HTH ! God bless

big fred · Jul 22, 2011

I always get a kick out of people that say things like "drive a 8 ft ground rod in the earth to 6 inches below grade". Those people obviously don't live in my neighborhood. I managed to get my 8 ft ground rods driven so that less than a foot was sticking out, then cut it off at that point. I'm sure that it's probably "Z" shaped underground where it's bent around the rocks I was trying to drive it thru. I've pulled t-posts that I'd driven 3 ft into the earth and they were bent about 20 degrees due to rocks.

Bob Bancroft · Jul 22, 2011

INDEED!
In my younger days I remember driving them for my electrician father in law once. He didn't bother to tell this young person about driving them in sideways, apart from one another, rather than trying to go vertical! Did cut some off with a hacksaw. That wasn't much easier than the driving! I imagine he enjoyed the whole thing!
With the two houses I've built, I was able to bury them during excavation. Then when I put up a drying bin in 1988 driving them in more horizontally(away from one another) than vertically worked well.

teddy52food · Jul 22, 2011

Does going sideways provide a proper ground when it gets dry???

big fred · Jul 22, 2011

The rock problem here is with the rocks the glaciers deposited, not ledge like they have back east, so going sideways doesn't help. The rocks are pretty randomly distributed.

Bob Bancroft · Jul 22, 2011

Glacial till with random rocks here too. But chances of getting straight down through this subsoil with the consistency of concrete(plus the random rocks)is virtually impossible. So going sideways is still a better bet.

Bob Bancroft · Jul 22, 2011

See my reply to big fred- plus- our prevailing concrete like subsoil holds very little moisture. We have good topsoil, just not much of it. So our soil and crops cannot well tolerate too much, and not enough rain. Most of this ground was artificially drained years ago by hand, quite shallow(about 2 feet) using stone, and later, tile.

Ken-Pa · Jul 22, 2011

Well you have a point , but whenever I was in business & doing services , my inspectors requirements for all 8' to be used . If it couldn't all be driving into the earth , he wanted it bent parralell with the ground in a trench & uncovered so he could see it . He always examined the end of the rods to se if they had been cut off too . I had worked in our campgrounds installing services & very few rods could be buried completely , so I did have to bend a few . God bless

big fred · Jul 22, 2011

After several hours of pounding mine thru the rocks, you couldn't even identify the original end, it was so badly mushroomed. I cut it off, banged on it some more to disguise the fact it was cut and called it good. Inspector didn't even look at it, except to verify I had them the proper distance apart.

Electrical questions??

IaGary

Well-known Member

Ken-Pa

Member

big fred

Well-known Member

Bob Bancroft

Well-known Member

teddy52food

Well-known Member

big fred

Well-known Member

Bob Bancroft

Well-known Member

Bob Bancroft

Well-known Member

Ken-Pa

Member

big fred

Well-known Member

Similar threads