Conduit fill

[blueheels2]

I have 100' of 1" PVC installed underground. Easiest thing to do but not the cheapest would be to finish this raceway and pull thwn into the conduit for this installation. But customer wants cheap. Other option is pull 6/3 UF into the conduit and not finish it off. I have 6/3 in hand and it will fit in 1" PVCs but I'm not sure I could pull it 100'. Maybe with lots of lube. Question is it even legal. Diameter of cable is listed as 1223 mils by 361 mils but not sure how to convert that to internal diameter of PVC. Thanks

 

[infinity]

You would take the widest dimension of the cable and convert that into an area as if it were round. Then you would see if it will fit in the raceway. Since it counts as a single conductor your fill can be up to 53%.

 

[kec]

Question to you is how many more feet of PVC is needed to finish run?

 

[ActionDave]

......Other option is pull 6/3 UF into the conduit and not finish it off. I have 6/3 in hand and it will fit in 1" PVCs but I'm not sure I could pull it 100'.

The odds of this being done successfully are slimmer than the odds of me making out with my ninety-three year old mother-in-law. If you put a gun to my head and tried to make me choose one or the other I would grab the trigger on the gun and pull it.

 

[blueheels2]

Question to you is how many more feet of PVC is needed to finish run?

100’ under a boat dock.
We are in NC so 555 doesn’t apply to single family dwelling because of amendments to the code.

Thinking about it I’m probably just going to finish the raceway. I’d either have to feed or pull standing in 4’ of water and that doesn’t sound like a good time. Labor saved not running the conduit is going to be lost in labor spent pulling the cable through the conduit I imagine. It would be tough to apply lube. Conduit comes out under the dock where bottom of the lake to bottom of the dock is 2’. If you walk out 20’ feet you can stand a work it .

I do t even like thinking of the logistics of that.

 

[LarryFine]

The odds of this being done successfully are slimmer than the odds of me making out with my ninety-three year old mother-in-law. If you put a gun to my head and tried to make me choose one or the other I would grab the trigger on the gun and pull it.

I'd have to see a picture of her before deciding.

UF in PVC has to be the hardest pull we ever face.

When I do it, I cheat and push/pull on one stick at a time.

 

[wwhitney]

I have 6/3 in hand and it will fit in 1" PVCs . . . Diameter of cable is listed as 1223 mils by 361 mils

1" Schedule 40 PVC has an inside diameter of 1.029", or 1029 mils. So if you have some 6/3 cable on hand that fits inside 1" PVC, the cable is not 1223 mils wide, as that wouldn't fit inside a 1029 mil circle.

Cheers, Wayne

 

[blueheels2]

1" Schedule 40 PVC has an inside diameter of 1.029", or 1029 mils. So if you have some 6/3 cable on hand that fits inside 1" PVC, the cable is not 1223 mils wide, as that wouldn't fit inside a 1029 mil circle.

Cheers, Wayne

Yeah I’ll have to go back and look what I stuck in the conduit.

 

[infinity]

1" Schedule 40 PVC has an inside diameter of 1.029", or 1029 mils. So if you have some 6/3 cable on hand that fits inside 1" PVC, the cable is not 1223 mils wide, as that wouldn't fit inside a 1029 mil circle.

According to Southwire their 6/3 UF is as stated in the OP 1223X361 mils so that ends the discussion.

 

[wwhitney]

According to Southwire their 6/3 UF is as stated in the OP 1223X361 mils so that ends the discussion.

Well, has 6/3 UF always been flat, or is there old stock 6/3 UF that was round?

Cheers, Wayne

 

[ActionDave]

I'd have to see a picture of her before deciding.
.

You don't want to do that. Some people have never recovered.

 

[tthh]

Popular Spanish expression "Lo barato sale caro" -- the cheap comes out expensive.

 

[blueheels2]

Well, has 6/3 UF always been flat, or is there old stock 6/3 UF that was round?

Cheers, Wayne

So I went back outside and checked . I was wrong. I was using a piece of 8/3. And as tight as that is it is guaranteed 6/3 will never fit.

 

[wwhitney]

So I went back outside and checked . I was wrong. I was using a piece of 8/3. And as tight as that is it is guaranteed 6/3 will never fit.

If it's flat 8/3 UF (maybe that's the only kind) that matches Southwire's, then it's 1059 mils across. So you must have had to squeeze it a little to get into your 1029 mils ID conduit, assuming you used Schedule 40.

Question is it even legal.

One cable or wire in a conduit can have an area fill of 53%. Area goes as the square of linear dimension, so that's a linear ratio of sqrt(53%) = 72.8%. That means your single wire or cable can have a diameter/width up to 72.8% * 1029 mils (if Schedule 40 1" PVC) = 749 mils.

Cheers, Wayne

 

[Tulsa Electrician]

I have 100' of 1" PVC installed underground. Easiest thing to do but not the cheapest would be to finish this raceway and pull thwn into the conduit for this installation. But customer wants cheap. Other option is pull 6/3 UF into the conduit and not finish it off. I have 6/3 in hand and it will fit in 1" PVCs but I'm not sure I could pull it 100'. Maybe with lots of lube. Question is it even legal. Diameter of cable is listed as 1223 mils by 361 mils but not sure how to convert that to internal diameter of PVC. Thanks

Pie R squared (R²). Is what you need for area inch squares (in²). Then you can go to the tables in chapter 9.

Since the cable is larger in diameter on one side than the other you use the larger. 1223 mills or 1.223 inches. 1- mill = .001 inch
1223*.001= 1.223 or just move decimal three places to the left on the mill number.

Then take the diameter and turn that into radius or 1/2 the the diameter.
1.223/2= .6115r
Then we square that or take .
.6115*.6115= .37393225 this is radius squared
Take that times pie.
.337393225*3.141592= 1.74742

Since chapter 9 table used three decimals use 1.747

Now you can compare that to the number in table for 1- wire 53% fill of .441 for 1" sch 40 PVC.
As you can see not code compliant.
100% fill is .832 which is to small as well.

So for a short cut as mentioned your diameter for one inch is 1.029 in and you cable is 1.223 in

I like to use for math in field and testing for these kind of questions.
Formula, D² * .7854 much easier
The .7854 is pie /4
This way it's takes radius out of the question and mistake in math. If you forget to take D and turn into R.

Then you can size raceway.
One wire @53% with an area inch squares of 1.747 in schedule 40 PVC would be.
2.5" @ 2.488 in²
If you choose 2" @ 1.744 in² you would miss the test question.
You have to use three decimal places.

Hope that explains how to figure.

 

[AC\DC]

if he does not finish the conduit is it a sleeve and not a race way, does conduit fill not matter then
chapter 9 table 1 note 2 says apply only to complete conduit runs
OP said he was not finishing conduit run so pull away

 

[LarryFine]

I came up with 2.5" in my head by approximately doubling the 1.223".

 

[Tulsa Electrician]

if he does not finish the conduit is it a sleeve and not a race way, does conduit fill not matter then
chapter 9 table 1 note 2 says apply only to complete conduit runs
OP said he was not finishing conduit run so pull away

I read that. I was answering his question on how to calculate raceway fill not sleeve size.
For sleeve size I would not choose a internal sleeve diameter smaller than the cable it protects.

With a sleeve in OP case using 1" PVC and assuming 90 degree bends 340.24 would still apply.
5 x dia for minimum bending radius.
You can not control the diameter to radius in an underground pull with factory 90's. There for the minimum sleeve size would be based on table 2 chapter nine for 1.223x5= 6.115r or 1-1/4".
I would also look at the minimum dia sleeve size for the cables major Dia or 1-1/4" @ 1.360 Dia.

Damage to cable most likely using 1" PVC ,square peg round hole.

 

[LarryFine]

Always remember the first rule of conduit: The I.D. must never exceed the O.D.

 

[kwired]

if he does not finish the conduit is it a sleeve and not a race way, does conduit fill not matter then
chapter 9 table 1 note 2 says apply only to complete conduit runs
OP said he was not finishing conduit run so pull away

True but pulling a cable through a 100 foot long sleeve you might want to consider the typical fill rules anyway or it may be a pretty difficult pull, particularly if there is any bends.