Pipe fill calculation for service

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ctaylo360860

ctaylo360860

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Installing a 200a service, and a 100a remote distribution panel.

Trying to make sure I used right tables to get my pipe fill calculations.

The service entrance conductors will be 3/0 cu thhn/thwn. I used value in table 5 and got .2679x3=.8037
I then went to table 4, imc, over 40% and the smallest raceway I would be able to use is 1-1/2imc .890

I then need to size my raceway for the remote distribution panel feeders.

My supply house only stocks 1/0,1/0,2 aluminum as 8000 type use-2 or rhh or rhw or rhw-2. i plan on running my own #6 cu ground
I used table 5a for aluminum
1/0=.1963x2=.3926in2
2=.1194in2

The #6egc should be found in table 5 and has an area of .0507 in2
Add all those areas together and you get .5627in2

I went back to table 4 ,rigid pvc sched 80, over 40% and found the smallest race way I could use is 1-1/2 .684

Basically wasn’t sure what table to use for the aluminum conductors I’m using as there are various Charts in table 5 that say rhh,rhw,rhw-2

Thanks I’m advance for any and all help!
 

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Didn't check your math, and no comment on which table to use for the Al conductors, but the overall method is correct. Assuming by "over 40%" you mean "over 2 wires = 40%".

But I wanted to add that if you have the wires on hand, you can always measure their OD with calipers, and then use pi * r2 to determine their area. Or use the manufacturer's data sheet to get the OD.

Cheers, Wayne
 
wwhitney said:
Didn't check your math, and no comment on which table to use for the Al conductors, but the overall method is correct. Assuming by "over 40%" you mean "over 2 wires = 40%".

But I wanted to add that if you have the wires on hand, you can always measure their OD with calipers, and then use pi * r2 to determine their area. Or use the manufacturer's data sheet to get the OD.

Cheers, Wayne
Click to expand...
Thanks, yeah I figured they’re in 5a because the southwire brand ihave says compact conductor and pretty much the same markings, however the encore wire doesn’t say compact conductor…

Yes that’s what I meant by the over 40% thanks for the tip I may have to try that!
 
ctaylo360860 said:
....
My supply house only stocks 1/0,1/0,2 aluminum as 8000 type use-2 or rhh or rhw or rhw-2. i plan on running my own #6 cu ground
....
Click to expand...
That appears to be a cable or cable assembly, and you need to get the area or OD from the cable manufacturer, or measure the cable to do the wire fill calculations. Note, that if this is a cable or cable assembly, the maximum permitted fill is 53%, not 40%.

Also the feeder will need an additional conductor. Two ungrounded, a grounded, and a grounding conductor.
 
ctaylo360860 said:
southwire brand ihave says compact conductor and pretty much the same markings, however the encore wire doesn’t say compact conductor…
Click to expand...
Southwire says their 1/0 "Aluminum RHH, RHW-2, USE-2" has 0.504" OD, while Encore says theirs has 0.496" OD. So the Encore is also compact conductor.

www.southwire.com

Aluminum RHH, RHW-2, USE-2 with Alumaflex® Brand Conductors | Southwire

Choose Southwire for reliable Aluminum RHH, RHW-2, and USE-2 cables with Alumaflex® Brand Conductors.
www.southwire.com www.southwire.com

Encore Wire Corporation

Type USE-2 or RHH or RHW-2 cables with Aluminum Alloy 8000 Series conductors are suitable for use in conduit and raceways installed underground in wet locations, and where
www.encorewire.com www.encorewire.com

Cheers, Wayne
 
don_resqcapt19 said:
That appears to be a cable or cable assembly, and you need to get the area or OD from the cable manufacturer, or measure the cable to do the wire fill calculations. Note, that if this is a cable or cable assembly, the maximum permitted fill is 53%, not 40%.

Also the feeder will need an additional conductor. Two ungrounded, a grounded, and a grounding conductor
don_resqcapt19 said:
That appears to be a cable or cable assembly, and you need to get the area or OD from the cable manufacturer, or measure the cable to do the wire fill calculations. Note, that if this is a cable or cable assembly, the maximum permitted fill is 53%, not 40%.

Also the feeder will need an additional conductor. Two ungrounded, a grounded, and a grounding conductor.
Click to expand...
correct and it has to have the egc upsized since I had to use 1/0 instead of 1 aluminum… I thought about running triplex instead of my own ground but I have to call and see which is the cheaper route… thanks for the help and the 53% tip!
Click to expand...
 
wwhitney said:
That would apply if there's an overall outer sheath. But there's no overall outer sheath and the conductors are just "plexed" together, then it can be treated as individual conductors?

Cheers, Wayne
Click to expand...
Okay so the 53% rule can only be used if there is an outer sheath, but because mine are plexed together I have to follow the 40% rule?
 
wwhitney said:
Southwire says their 1/0 "Aluminum RHH, RHW-2, USE-2" has 0.504" OD, while Encore says theirs has 0.496" OD. So the Encore is also compact conductor.

www.southwire.com

Aluminum RHH, RHW-2, USE-2 with Alumaflex® Brand Conductors | Southwire

Choose Southwire for reliable Aluminum RHH, RHW-2, and USE-2 cables with Alumaflex® Brand Conductors.
www.southwire.com www.southwire.com

Encore Wire Corporation

Type USE-2 or RHH or RHW-2 cables with Aluminum Alloy 8000 Series conductors are suitable for use in conduit and raceways installed underground in wet locations, and where
www.encorewire.com www.encorewire.com

Cheers, Wayne
Click to expand...
So 3.14x.496 to the second power =.7724insquared that’s my area for one 1/0 conductor of my cable?
 
ctaylo360860 said:
Okay so the 53% rule can only be used if there is an outer sheath, but because mine are plexed together I have to follow the 40% rule?
Click to expand...
Well, that's my understanding but it bears confirming.

Also, for plexed conductors you are better off with the 40% rule than the 53% rule, because the packing efficiency of circles in circles is less than 40/53.

Circle packing in a circle - Wikipedia

en.wikipedia.org en.wikipedia.org

Cheers, Wayne
 
1/0 area should be .1931x2=.3862in square
#2 area should be .1181inches square
#6cu area should be .0507 inches square
Add that all together and I get a .555inch square for my cable. Which means 1-1/2 sh ed 80 pvc is the smallest raceway could get away with
 
texie said:
A cable made up of multiple conductors whiteout an outer covering are to be considered individual conductors for conduit fill purposes. So the 40% rule would apply. Chapter 9 Tables, Note (9).
Click to expand...
Thanks for the clarification on that! Man I’m always learning something new on the forum! You guys rock!
 
If I went with quAdplex I would have to go up to 2inch
.1931x3=.5793

.5793+.1181=.6974insquared and 1-1/2 sched 80 at 40% is only .684
 
ctaylo360860 said:
1/0 area should be .1931x2=.3862in square
#2 area should be .1181inches square
#6cu area should be .0507 inches square
Add that all together and I get a .555inch square for my cable. Which means 1-1/2 sh ed 80 pvc is the smallest raceway could get away with
Click to expand...
You don't add the cross-sectional areas of multiple conductors that will be threaded into a conduit. I learned that a long time ago as I damaged cables using that way. Best for you to get the biggest diameter in the group of cables and solve for the equivalent overall diameter of the cables. There is a factor used to multiply the conductor diameter depending on the number of conductors circumscribed by the walls of the conduit. You have three individual conductors and your factor will be 2.155. The diameter of circumscribed conductors will be = diameter of one representative conductor X 2.155. Then apply the fill factor as if you are threading only one conductor( 53%)
 
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