Underground Conduit Install Question

[Balvar24]

I have to make a 90 degree turn below grade for my primary feed.

Local PoCo said I couldn't install fittings below grade, but I could install the conduit in a sweeping ditch.

Anyone ever tried this with 3" PVC? I've got about 250' to install to get to the shop (60x40), but I'm concerned about how many feet the turn will take up.

Thanks.

 

[bmxdad]

Can't you get a 3" 90 deg sweep ... pvc?

 

[MagKarl]

3" will bend fine into a curving/sweeping trench as long as the radius is large. You will need elbows though for tight turns. My power company was good with 360 degrees of total fittings in the line and I needed all of it in my case.

Consider using two 45's when you get to the shop, they can work better than a 90 when you're working around a footing as you rise up from the trench depth.

 

[tyme2par4]

Is this a requirement so that they can pull the service wire?

 

[Kaizen]

That makes no sense. Unless your area requires a flexible one piece duct of some kind that runs the whole length. gluing pipe together is same as a fitting. they expect you to surface into a pedestal for any time you want to turn direction?

 

[Norcal]

Just use a long sweep 90.

 

[Balvar24]

Thanks for all the helpful responses so far.

Local PoCo guy said no fittings below grade except for riser at the pole and meter base.

He said I could naturally sweep the straight pipe in the ditch.

I read online that you can bend at a radius of approximately 300 x pipe diameter.

Anyone done this before?

 

[mz44]

Get a torch or heat gun and heat the pipe up it will bend easily then let it cool.

 

[dw1]

Thanks for all the helpful responses so far.

Local PoCo guy said no fittings below grade except for riser at the pole and meter base.

He said I could naturally sweep the straight pipe in the ditch.

I read online that you can bend at a radius of approximately 300 x pipe diameter.

Anyone done this before?

They make PVC heaters to bend it accordingly, but it would be less hassle to do as Norcal and others have stated and use a radius 90*. The power co here requires them on anything that they are pulling wire through, they don't care what you use on your side- if you are pulling the wire

 

[Aceman]

The power company only wants 90 degree sweeps at the ends of the run.

Dig the ditch in such a way that it's as straight as possible. If you can't dig it perfectly straight, use long gradual bends in the ditch and you will be able to bow the 3" to fit. You should not need to heat the conduit to bend it if you dig the ditch correctly.

Post pics of the path the conduit needs to run if you want more site specific answers.

 

[alfredeneuman]

Try the PoCo first
Some power companies post their "Requirements for Service" as a .pdf file online.
(as an example : https://www.sce.com/nrc/aboutsce/regulatory/distributionmanuals/esr.pdf )

It tells you all that you need to know, and more .

Don't try to heat and bend 3" on your own. Use factory sweeps.

 

[Balvar24]

Has anyone ever dug their ditch with a radius rather than straight and installed the pipe in it, giving the pipe a gradual sweeping change in direction?

The Power Company said no fittings were permitted and recommended this means of installation.

Has anyone tried this?

 

[Wirepuller]

Maybe I misunderstood your OP. This is the service to your building correct? If so the utility should take a hike. NEC covers you there.






This a large service I ran a month or so ago. If you dig the trench large enough at your bend points the pipe will fall into place without the use of sweeps. I try not to use sweeps unless I have to. Most utilities around my area require long radius rigid steel at the pole for the primary side and we can use standard radius PVC into the pad or transformer vault. Anything is allowed on the secondary side that's for the wiring inspector to deal with.


Sent from my iPhone using Tapatalk

 

[Aceman]

Has anyone ever dug their ditch with a radius rather than straight and installed the pipe in it, giving the pipe a gradual sweeping change in direction?

The Power Company said no fittings were permitted and recommended this means of installation.

Has anyone tried this?

You are overthinking this.

Myself and others do this for a living, bowing conduit into a radiused ditch is done all the time. Here are some more pictures for proof it can be done, three 4" pvc's for an 800 amp service that we bowed into place for the power company.

 

[Cmreschke]

Also fyi, a sweep 90 or a factory elbow is by definition NOT a fitting. A fitting would be an LB or the such. The poco may be just miscomunicating this.
A factory elbow or sweep 90 is just conduit with a bend from the factory, unless you bent it yourself. Either way still just conduit and not a fitting.

 

[bmxdad]

Has anyone ever dug their ditch with a radius rather than straight and installed the pipe in it, giving the pipe a gradual sweeping change in direction?

The Power Company said no fittings were permitted and recommended this means of installation.

Has anyone tried this?

I did, but it was more of a bend. Went around a concrete pier. BIL had a pipe heater and we used that. Why do you need to make a 90 degree turn?

I wouldn't call a 90 degree sweep a fitting ... maybe they are talking about a j-box or something similar? You can get different radius sweeps too ... is there a minimum radius they want?

 

[dw1]

As everyone is showing, the pvc pipe runs are forgiving, you can bend them accordingly by using your ditch. I always try to dig the ditch in a straight line as others have stated also, but sometimes you just cant, this run had a 45* bend at both ends, but just dug the ditch that way, did not use any fittings ect.

 

[alfredeneuman]

Maybe I misunderstood your OP. This is the service to your building correct? If so the utility should take a hike. NEC covers you there.

Where I live and work the utility has the final say on anything on their side of the service connection. The NEC, in 90.2 actually says under "Scope" that it is not covered.

(B) Not Covered. This Code does not cover the following:

(5) Installations under the exclusive control of an electric
utility where such installations
a. Consist of service drops or service laterals, and associated
metering.

They have their own inspections, and unless it meets THEIR specs, won't supply service.

 

[wyliesdiesels]

Same around here.

And The NEC doesnt cover the line side of the service(before the meter underground/service lateral)...

If overhead the NEC stops at the weatherhead and splice point.

PoCos are governed by a different set of codes and rules.

 

[Balvar24]

Thanks guys. Trying to miss a retaining wall and wasn't sure how tight of a turn I could make. 75 ft radius is going to be tough, but I think I can get it.