SE cable, conduit protected...and other electrical service remarks.

Folks: First, I am not a sparky. I do my own electrical work, as we are allowed to do here. I follow the relevant Code provisions, pull permits, and submit it for inspection. I am in perfect agreement with any pros who look down on homeowners who do careless electrical work, as about 50% of that which I've seen is questionable and 10% is abhorrent.
Okay. At present, I am upgrading my service from a relatively nice 60A fuse box to a 200A CH series panel, which is a new job for me, and the usual practices around here leads me to wonder about some things.
First, around here, cable electrical services are usual. It is also common to run the SE cable in a short length of conduit below the meter socket, through an LB into the house, because the lower length is prone to physical damage, from cars if on a driveway, from the wild hedge trimmer if not. Theoretically the PVC is Sch 80 but frankly a lot of houses have whatever Big Blue or Big Orange carry.
Here's the problem: SE cable is not the greatest thing for use inside raceway. If the raceway is big enough, the code allows it, but it's stiff and hard to pull and certainly not as suitable as, say, XHHW. Unfortunately, I can't use that...the local AHJ doesn't want raceway leading right from the meter pan to the box, because it's too easy for water to get in.
I suppose my own question is answered...stop the raceway just inside the wall & pull in the SE cable. Sigh. I just don't like it. Has anybody else run into this problem?
What I would really like to do is run a Sch 80 PVC mast with XHHW conductors, and Sch 80 conduit from the meter pan to box. Unfortunately they look at you like a madman when you ask for XHHW around here and suggest THHN for use in a conduit mast. I will probably have to go with the cable, which does not make me happy...not because I hate cable. The cable's fine. It's the watertight connector that bothers me. You're not supposed to trust these to actually *be* watertight, and you are to press sealant around them to keep water out. Alas, this sealant never lasts long -- from expansion or sun or whatever, it tends to dry out and not stay stuck to the cable and connector, and seems just like a major kluge to me. And right below the watertight conn. the nice aluminum conductors run to the nice lugs, with a coat of Penetrox to keep the aluminum from attempting to return to nature. Urk. And this is supposed to last for 30 yrs. without maintenance...and frankly, it usually works very well, but...the whole business makes me very unhappy.
Cordially yours: Gerard P.
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While you certainly need to adhere to the AHJ in your local, but, personally I'd use a 2" pvc standpipe into the meter and 2" sch 80 from meter to panel which is technically equal to steel, then I'd use #2/0 copper THWN as THHN is not NEC compliant in wet locations and copper will last longer and it's easy to pull. You will however need a mortgage to buy it right now

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RBM (remove this) wrote:

RBM:
I like that idea a lot. A. smaller wire B. not depending on one-shot inaccessible dope for corrosion resistance. Unfortunately the local electric suppliers don't stock even Cu THWN that big as it would be a rare sale at best ...there's mostly cable services around here, too. Graybar might have it, but I don't know how small a piece they'd be willing to sell. I will check tomorrow.
Of course, I'd still need to use cable from the meter to the box...unless I could convince the inspector otherwise. Cu SE cable is a completely mythical beast around here, even ore so than #2/0 Cu, and if I'm going to use #4/0 Al for that I might as well use it for the mast, as they both end up buried in the meter pan. Hmf. It is a quandary.
Cordially yours: Gerard P.
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I would think they should allow you to fill the entrance condulet with silicone to exclude water. Are there no electrical supply houses in your area?

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RBM (remove this) wrote:

RBM:
Yup, there are. I just found out that Graybar could order XHHW or THWN-insulated 2/0 Cu for me from their Cleveland office... (@ $2.95 per foot, vs. $1.10 for Al, ooooh the pain...) but believe it or not, they're the only ones I can find. This is a strictly Al SEU-serviced town, as far as homes are concerned. I am going to end up looking a proper chump for using copper in conduit. Copper SEU cable of any kind is unobtainable locally even from Graybar.
I keep running into funny stuff like this. The local utility's standards literature demands an insulator fixed to the house structure with a 5/8" bolt and nut...got plenty of weird looks asking for anything like that, so I called up ye power company that be and was told that the usual screw-in insulator is fine. Gee, maybe they should mention that to their engineers. :)
Cordially yours: Gerard P.
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snipped-for-privacy@gannon.edu wrote:

You can use clear silicon caulk to seal the cable fitting and apply the Duct sealant that the inspectors prefer over it.
Be very careful about sizing the LB. Since your inspector obviously makes up the rules as he goes along ask him what size he will except. As for the weatherproof connector issue you can bring the cable into the bottom of the meter can if it is listed for that use. Who provides the meter enclosure in your area? If its you then buy one that is suitable for overhead or underground entry and bring the supply cable into the bottom of the can. That approach may get your inspector to except the raceway all the way to the Service Disconnecting Means enclosure.
If you do run raceway to the service enclosure be aware that the internal depth of the LBs are governed by the provisions of section 314.28 Pull and Junction Boxes and Conduit Bodies. The exception to subsection A (2) requires LBs to have a depth equal to the value called out in Table 312.6(A). For 4/0 conductors that table requires a 4 inch distance between the back entry to the LB and the cover. You may need to use a mogul LB or an over sized LB with reducing bushings. If you run the USE cable through the LB it may need to be even larger.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
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