Electrical Wiring in the Home/wiring to outbuilding


outbuilding moved from Ga. to Al. with accompanying three 4/0 cables with a 150 amp panel to serve building. Building now located about 50' farther than when in Ga. From the panel in the building,I ran the wire through 2" conduit to a 90 degree sweep,continuing under the building (crawlspsce) with conduit attached to floorjoices with straps.When exiting from under the building used two 45 degree connectors with straight piece long enough to enter ground about 18". Continued with wire through conduit to a point about 15' from building. My original thought was to splice into the needed length of additional wire with the use of a "waterproof"  underground connection box. From this point, this whole project has become a fiasco (mostly due to MY own ignorance,admittedly).From 3 0r 4 different acquaintances(of course, with 3or 4 differing opinions),all former electricians,the one resounding thought is this. "Bite the bullet" and purchase the wire to make it one solid run.The next little revelation was that this type wire could be buried directly in the ground, thus eliminating a lot of the hassle involved with running it through conduit.NOW,for one more point of aggravation (and confusion).Someone gave me lenth of 4/0 wire  (at this point ,I was still considering splicing into underground junction box).Began feeding this cable through the conduit @ source panel into a 90 degree sweep, through an extended piece of conduit going under plumbing connections to septic system, pulling wire through to a point where splice in junction box WOULD have been made. Became a mute point, because wire was about 3' short.And the reason for the difficulty in pulling this wire through the 2" conduit, was the fact that it was a 4 CONDUCTOR cable, which I had paid no attention to until after the fact.  Pardon my lengthy query, please. I have explained all of this , hopefully for clarity,finally to ask a couple of questions.Would it be legal and safe at this point to remove all this existing wire, and replace it with 3 strand 4/0 cable? Also, can I pull the wire through the existing conduit,leaving the remainder of the wire exposed, if I  seal the open ends of the conduit?

Have you considered putting the subpanel at the place where the wire ends, 15 feet away from building, and then run a 2" conduit from that to the building with your circuit wires in the 2" conduit (or how ever many conduits you need)?

If you have overhead supply wires from the utility company you will notice they make a splice right before your weatherhead. So can you do a splice? Yes.

But instead of burying a box why not put a box on a post and bring the wires up to the waterproof box above ground?

If the splice is done correctly you should have no problems. But is must be done correctly.

Otherwise, you have to pull all the wire back out and run a new length that reaches panel to subpanel.  
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Electrical Wiring in the Home

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Greg Hughes


Troubleshooting electrical including appliances and HVAC.


34 years of experience.

Both college and tech schools in this field.

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