In-Ground Pull Box Problems

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Jon456

Jon456

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Colorado
We have two in-ground pull boxes. Both are Christy N36 concrete electrical boxes (17" x 30" nominal internal dimensions). Each appears to have problems with the way the wire was pulled through the box. I'd like to get feedback on the seriousness of the problems, how they could have been avoided during construction, and how we can resolve the problems now.

Pull Box #1:

IMAG1446.jpg


This box contains a single run of (3) 500 MCM CU-XHHW feeders carrying 3-phase 480VAC (no neutral) in 4" PVC conduit. In this box, the way the wires are looped means that the box lid is in contact with the tops of the wires. The box lid is composite (plastic top surface & cast concrete bottom surface) so the rough concrete bottom-side of the lid is rubbing against the insulation of the wires. There is some light scuffing/abrasion of the insulation where the wires contact the lid.

Pull Box #2:

IMAG1448.jpg


This box contains two runs of (3) 500 MCM CU-XHHW feeders carrying 3-phase 480VAC (plus some additional runs of wire carrying DC from a set of solar panels); each run of feeders is in 4" PVC conduit. One set of feeders (center-top in photo) is very tightly looped to a very small radius. I'm concerned that this may reduce the longevity of the insulation. The other set of feeders is rubbing against three sides of the concrete box (top, right, and bottom sides in the photo). Also, the sand fill in the bottom of the box is up to the level of the opening of at least one conduit.

Additionally, this set of feeders is spliced but the shrink-wrap splice covers do not appear to be waterproof (no hot-melt adhesive is visible).
 
I think those handholes look like a million other handholes I've came across that, despite being ugly, functioned just fine.

Box 1. I'd bend the conductors down so they weren't making contact with the lid.

Box 2. I wouldn't worry about the tight bends or the contact with the sides of the box. If it really bothers you, slip some mastic pads in between the wires and box. Also, if you can remove some of the sand from the box, then you can duct seal the conduits to keep dirt and debris out of them. For the heatshrink without the adhesive, I would brush some scotchkote around the ends of the heatshrink to make them weatherproof.

For the record, we've installed MCC's over concrete troughs or gutters with wires chasing through them for years without one issue. I don't see your wires touching the sides of a concrete handhole as much different.
 
I'd be pleasantly surprised to see the the ends of the conduit actually are above grade and also have bell ends on them.
 
plumb bob said:
I'd be pleasantly surprised to see the the ends of the conduit actually are above grade and also have bell ends on them.
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Above grade or just above the water table or dirt level inside? I see very few handholes with the cover actually above grade, let alone the conduit ends inside.
 
GoldDigger said:
Above grade or just above the water table or dirt level inside? I see very few handholes with the cover actually above grade, let alone the conduit ends inside.
Click to expand...

Above grade of the bottom of the box is what I meant I guess! I've opened a few hand holes where it appeared the conducters had been directly buried. Over the years mud, dirt, debris had covered the tops of the conduit because they didn't stub quite far up enough into the box.
 
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