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Providing expansion fitting for RMC at meter.

926 Views 19 Replies 11 Participants Last post by  ohm it hertz
I went on an estimate today and found this:

Plant Brickwork Brick Clock Gas

Gas Font Motor vehicle Gauge Machine

Turns out I can keep the existing feeders for the upgrade. I want to install schedule 80 PVC with an expansion fitting so this doesn't happen again. Can I cut the rmc just above grade, slip an rmc compression fitting on there, and thread a PVC female threaded adapter? From there glue in a cut of PVC to an expansion fitting? Any issues doing this? This would effectively separate any bond the conduit has between the transformer pad and the meter. Would I then need to bond to the can between the rmc and the new meter?

Or if there's a better way to do this which I did not mention, please share.

It's not every day I find services fed underground in RMC.
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Did you dig it up ? It could be direct burial cable and as post 5 said it could be just a sleeve. It was very typical around here 30 years ago +/-.
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For this pipe to move that much, it would have to be frost heaving, not temperature - you could heat the rigid with a torch and it wouldn't expand that much. If it's frost heaving, an expansion fitting might help, but if that heave isn't straight up and down, the fitting might bind. So you might go to all that expense and trouble and it still gets pushed around.

Is it really frost heave? You wonder what you'd find if you exposed the underground a little. I don't see a jacket so I don't think it's a stub around cable, but if that's the case, just securing the conduit might fix the issue. If it's pipe all the way, you might prevent the heaving if you dig around the pipe and put some sand / gravel.

What's going on there, am I missing something or I don't even see mounting screws inside the meter can, and I don't see any strap on the rigid? It's like the meter's set on a pipe stake that also happens to contain the utility service.

I wouldn't be surprised with everything unsecured, it just settled / sank. That could explain the "S" shape curve of the SE too. Yep, I think I just convinced myself, I think it just sank / settled.
Nothing is fastened because the siding guys removed everything so they could install siding. That would be my guess.
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Okay, I never thought of that. Around here the ground doesn't heave much, probably because of all the rocks in the soil. They say the Ozark Mountain range is the oldest in the US at 1.4 billion years. Unless you live in a river bottom, your soil can be as much rock as it is dirt. When you go to dig a hole, you take a pick, a rock bar, and a small shovel for any dirt you find... I'm retired, but in 25 years I've only seen or installed expansion joints on conduit coming up to service on government jobs where the spec.'s require them. I've had to use lots of them on PVC in parking garages though, to keep if from pulling it apart in winter, and bowing out like spaghetti in the summer.
Some other reasons for expansion joints could be to account t for improper back filling. If the backfill is frozen or not tampered down it could eventually settle and take the conduit with it. Also frost heaves could take the conduit up and down.
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