Tricks for Identifying Existing PVC?

[FionaZuppa]

All about conduit fill for upsizing the wire for VD. Total circuit length is 540 ft total from source to load and back. That adds up depending on if, for example, I use #8's or #10's.

So 1amp is 540ft round trip? So ~270ft of ckt.
I am still however confused as to what you are doing. Replacing the old with new for bigger pipe? All new to the side of what's there? How much of 270ft is buried?
Bury sched 40, make the risers sched 80. Not clear to me how many feet you have to go from above grade to some connection point, but just figure from the turn up in the trench to above ground end point use sched 80. Done.

At retail sched 80 is about 1.8x that of sched 40 in 2", and about 1.6x for 1/2".

 

[ActionDave]

All about conduit fill for upsizing the wire for VD. Total circuit length is 540 ft total from source to load and back. That adds up depending on if, for example, I use #8's or #10's.

What's the application, voltage, and load in amps. 270' may not even be too far to use 12AWG. I've run farther than that for gate openers and well pumps or roots blowers for example and not had any trouble.

 

[electrofelon]

Depends...one of the State inspectors reminded us in a newsletter that if the 90 extends above 18” below ground level, it needs to be Schedule 80.

Code reference? Or is this an interpretation of "subject to physical damage"?

 

[FionaZuppa]

Code reference? Or is this an interpretation of "subject to physical damage"?

I think its the bury code part. When it's below say 18", sched 40 is ok, above 18" in a turn-up is a "riser" and should be sched 80. If the trench is say 30" deep and you do turn-up, it can be sched 40 from 30-to-18" but then should be sched 80 from 18" up & out, etc. Now, if it turn-up directly into a wall that protects the pipe........ then I dunno if sched 80 is needed at all. I thought sched 80 was to provide "self protection" for "exposed pipe subject to damage"?

 

[ActionDave]

I think its the bury code part. When it's below say 18", sched 40 is ok, above 18" in a turn-up is a "riser" and should be sched 80.

Where in the index or table of contents is the "bury code part"?

If the trench is say 30" deep and you do turn-up, it can be sched 40 from 30-to-18" but then should be sched 80 from 18" up & out, etc. Now, if it turn-up directly into a wall that protects the pipe........ then I dunno if sched 80 is needed at all. I thought sched 80 was to provide "self protection" for "exposed pipe subject to damage"?

Shouldn't this be in the 'un-bury code part" or the "not fully burried code part"?

 

[electrofelon]

Where in the index or table of contents is the "bury code part"?


Shouldn't this be in the 'un-bury code part" or the "not fully burried code part"?

The kitties want answers!

 

[Eddie702]

540' round trip/270' 1 way with 1/2" i think will be an issue unless you have some existing pull points

 

[Little Bill]

All about conduit fill for upsizing the wire for VD. Total circuit length is 540 ft total from source to load and back. That adds up depending on if, for example, I use #8's or #10's.

If you need 8 awg you might as well forget the 1/2".

 

[FionaZuppa]

Where in the index or table of contents is the "bury code part"?


Shouldn't this be in the 'un-bury code part" or the "not fully burried code part"?

??
Table 300.5

540' round trip/270' 1 way with 1/2" i think will be an issue unless you have some existing pull points

To be future-friendly, why not just 1,1.5, or 2" it?

Just for fun, 1/2" it and try a 3x #6 pull (even toss in a bottle of lube), the one who can get the furthest is the winner.

 

[synchro]

All about conduit fill for upsizing the wire for VD. Total circuit length is 540 ft total from source to load and back. That adds up depending on if, for example, I use #8's or #10's.

If you could use #8 for the whole 540ft it would have a 5% voltage drop with a 17A load at 20°C. But three #8's exceeds the fill limit for sch 80 1/2" PVC as wwhitney mentioned in your other thread.
A #10 for the hot and #8 for the neutral would fit, and it would have a 5% drop at 12.3A.

How much of the 540ft is in 1/2" EMT and how much in 1/2" PVC?
You could put two #6 in the EMT and a #10 hot, #8 neutral, and #10 EGC in the PVC.
Then if it was 2 #6 for 1/2 of the run there would be 5% drop at 17A.
If it was 2 #6 for 1/4 of the run there would be 5% drop at 14.3A, and so diminishing returns with that.

 

[FionaZuppa]

If you could use #8 for the whole 540ft it would have a 5% voltage drop with a 17A load at 20°C. But three #8's exceeds the fill limit for sch 80 1/2" PVC as wwhitney mentioned in your other thread.
A #10 for the hot and #8 for the neutral would fit, and it would have a 5% drop at 12.3A.

How much of the 540ft is in 1/2" EMT and how much in 1/2" PVC?
You could put two #6 in the EMT and a #10 hot, #8 neutral, and #10 EGC in the PVC.
Then if it was 2 #6 for 1/2 of the run there would be 5% drop at 17A.
If it was 2 #6 for 1/4 of the run there would be 5% drop at 14.3A, and so diminishing returns with that.

sched40 1/2" is ok for three 8's, but not in sched80? Then why not just go with 3/4" or 1". Done. Probably only a $30-40 diff in upsizing the pipe.
If the cost of upsizing the PVC is a deal breaker for bidder or customer, then skip doing the job.

 

[synchro]

sched40 1/2" is ok for three 8's, but not in sched80? Then why not just go with 3/4" or 1". Done. Probably only a $30-40 diff in upsizing the pipe.
If the cost of upsizing the PVC is a deal breaker for bidder or customer, then skip doing the job.

I had the impression that the 1/2" PVC was already there under a parking lot or something and the OP was wanting to reuse it if possible. But the OP didn't provide many details.

 

[FionaZuppa]

I had the impression that the 1/2" PVC was already there under a parking lot or something and the OP was wanting to reuse it if possible. But the OP didn't provide many details.

I went back to post #1, and I guess its plausible it's conduit re-use and just pulling some wires.

If it's possible to look down into the pipe where its connecting to that timer box, stick a small bore scope down in there and take a look, sched40 vs sched80 is fairly ez to spot. I always carry a USB bore scope with me, connects to my phone, I can then look, take video, or take a pic. I got one of the cheap ones from amzon, I think it was a flexible 6ft model.

With experience, tapping on sched40 vs sched80 will be known from the sound they make.

 

[Jerramundi]

What's the application, voltage, and load in amps. 270' may not even be too far to use 12AWG. I've run farther than that for gate openers and well pumps or roots blowers for example and not had any trouble.

I don't want to get into the specifics because there will likely be another post from me with more project details. I'm trying to keep this particular post just about identifying PVC Schedule's 80 vs. 40.

 

[Jerramundi]

If you need 8 awg you might as well forget the 1/2".

I've done some conduit fill math and there are various applications where #8 would fit in both Schedule 80 and Schedule 40, but again, trying to keep this thread simply about just any tricks to identifying 80 v. 40.

 

[Jerramundi]

sched40 1/2" is ok for three 8's, but not in sched80? Then why not just go with 3/4" or 1". Done. Probably only a $30-40 diff in upsizing the pipe.
If the cost of upsizing the PVC is a deal breaker for bidder or customer, then skip doing the job.

Long time customer that's given me a lot of great opportunities. Trying to do right by them. Just considering various options. The first general category being utilizing the existing raceways.. the second general category being replacing them.

 

[FionaZuppa]

Long time customer that's given me a lot of great opportunities. Trying to do right by them. Just considering various options. The first general category being utilizing the existing raceways.. the second general category being replacing them.

Are you re-using old pipe, is that the nature of this no-details project?
Just put a bore scope into the pipe from the "timer" box, you'll see if it's 40 or 80 faster than I can fart after eating Taco Bell
If the pipe you say is painted, so then it's exposed pipe w/o any further protections from damage, then it "should" be 80 if it was inpected off of an old permit, no?

And a real valid Q from me. If you re-use pipe to pull new wire, the whole thing is considered new install and you would have to show the pipe before burial, or is that kinda voided if say you can show it (the pipe) listed on a old permit & inspected?

 

[kwired]

My experiences is long run of 1/2 inch PVC is hard to pull even with no elbows. Not saying impossible, just be ready to have some fun use #8 so that after it stretches you still have at least 10 AWG left in the pipe

 

[ActionDave]

??
Table 300.5...

Uhmmm that's not the "bury part of the code". That's the part of the code that has General Requirements for Wiring. And there is nothing in that part of the code, or any other part of the code, that says anything about transitioning from sch 40 to sch 80 at a given depth.

 

[ActionDave]

I went back to post #1, and I guess its plausible it's conduit re-use and just pulling some wires.....

What part was it that makes it plausible? The part where he says, "The portion of PVC that is visible above ground is painted."
Or maybe the part where he says, "I was just wondering if anyone had any tricks for identifying existing PVC."
Or perhaps it's where he says, "The only (2) things I can think of are (1) dig down until I find some insignia on the PVC... or (2) disconnect/cut a section and measure the Internal Diameter (ID)."
Other than that I guess one could miss the context, but that is pretty much all of the words used to describe the conduit in the OP.