Have an electric gate to hook up, the former electrician ran his 2-2-4 URD from the house and stubbed it up close to the gate in PVC, the gate installers stubbed their THHN up in PVC next to his from their control box. Cut both off at grade and splice in a buried handhole enclosure? AL butt splices with rubber tape?
Spice THHN in buried handhole enclosure?
- Thread starter TimWA
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Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
Why not a pvc box on a 4x4 post just a little off the ground? Polaris connectors to splice with. Easy money....
Strathead
Senior Member
- Location
- Ocala, Florida, USA
- Occupation
- Electrician/Estimator/Project Manager/Superintendent
I am guessing because they didn't! To the OP, first, the wire would be THWN in this application. Most likely the wire is dual rated, THHN/THWN but since it is in a wet location the wire is THWN. This most often becomes important when you are figuring the ampacity. Regarding the splices, the NEC 2011 300.50B requires the splices to be "approved" for wet locations. I don't have my earlier code book right now, but there is something similar in it as well. The easiest way to do this is to buy silicone impregnated wire nuts. I have used red wire nuts and filled them with silicone, or dipped them in Scothkote and had no problem with the AHJ, but if the splices don't have a waterproof coating I would consider them illegal.
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
Huh?
He said both conduits are stubbed up near each other, why wouldn't a pvc box work?
A coupe of technicalities: as Strathead mentioned, hopefully the "THHN" is dual rated as "THWN" also and URD (without any other rating is not a acceptable NEC wiring method).
A "buried" box with splice is not accepted locally. A box flush with the dirt is acceptable and if there is any possibility of physical damage a Quazite (or equal) box is required. ( http://www.hubbellpowersystems.com/about/quazite/ )
Splices in such a box would be required to be listed for wet locations.
Cow's method is the one I see most often
A "buried" box with splice is not accepted locally. A box flush with the dirt is acceptable and if there is any possibility of physical damage a Quazite (or equal) box is required. ( http://www.hubbellpowersystems.com/about/quazite/ )
Splices in such a box would be required to be listed for wet locations.
Cow's method is the one I see most often
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Strathead
Senior Member
- Location
- Ocala, Florida, USA
- Occupation
- Electrician/Estimator/Project Manager/Superintendent
Strathead
Senior Member
- Location
- Ocala, Florida, USA
- Occupation
- Electrician/Estimator/Project Manager/Superintendent
For future reference... I didn't see a requirement for "listing" of the splices. I saw "approved". Did I miss something?
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
I figured you might of read it quick and thought they were cut off flush but I wasn't sure. No big deal.
My error. I often use the terms interchangable as we seldom approve anytying that is of the nature that a listed product is available,
Rampage_Rick
Senior Member
- Location
- British Columbia, Canada
I've had to troubleshoot buried splices at a golf course. The silicone filled wire nuts are junk, I might consider them for surface wiring 12V landscape lighting, but they just don't last.
3M brand grease tubes are the way to go. DBY up to #12 and DBR up to #10. They're about $3 each if you buy them individually, much cheaper if you buy them in cases of 25.
My other choice is Shake 'N Seal. An ES200S will handle a big split bolt, or you can use one tube to waterproof a handful of #12 splices in one go.
kwired
Electron manager
- Location
- NE Nebraska
Is the 2-2-4 URD aluminum like I suspect it is? Rubber splice tape is likely not water tight enough - especially for aluminum terminations. If this hand hole is subjected to filling with water it will not last long at all without a good sealing system like shrink tubing or shrink caps with intregal sealant. You did not say what size conductors were to be spliced to the 2-2-4.
Thanks, that's what made it tricky. The 2-2-4 AL URD triplex ran from the house needed splicing to #12 THHN/THWN so silicone wirenuts were out (at least any I've seen), shrink tube out also I expect, good luck sealing it on #12 single conductors.
I called an inspector and had him agree that I could use the AL butt splices with the rubber splice tape. However, that may not be the inspector I actually get so we'll see! Poly hand hole enclosure is open-bottom in gravel/sand so it will never hold water.
kwired
Electron manager
- Location
- NE Nebraska
Good luck sealing it well enough with rubber splice tape. Unless it is on top of a hill there is a chance of it filling with water even if just temporarily. If it is in a low spot it may fill with water any time there is significant rainfall.
- Location
- Massachusetts
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
To each their own. It's smaller than the big black control box for running the electric gate....
kwired
Electron manager
- Location
- NE Nebraska
Depending on layout of things it may be able to be strategically placed where it is not that noticed, as well as the big black control box. Quazites are not cheap, not having splices below grade is an advantage also.
Thanks for your thoughts. The size variation across the splices was the main issue. Shrink tube that goes over a #2-wire butt splice I believe isn't sealing down to #12. At least the rubber tape is adhesive and applied carefully is pretty dang well sealing, and protective. The splices are suspended toward the top of the box, the drainage location is gravel/sand hilltop and will never see water accumulation. Imperfect but workable I hope.
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Yes, handhole enclosure cover at grade definitely preferable to a jbox popped up on a little post. I did consider attaching a jbox to the side of the gate control enclosure and nippling through, but even that is pretty ugly.
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kwired
Electron manager
- Location
- NE Nebraska
I did a gate with stone walls on either side of it. We put control box, breaker panel and other stuff on back side of stone wall and there are bushes/other plants that hide it well enough nobody notices - and they are not violating 110.26 either.
- Occupation
- Licensed Electrician
Add some Skotch Kote and a layer of vinyl tape and you should be good.
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