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04-17-2012, 11:00 PM
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#1
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De-Rating
Can I put 3 sets (parallel) of 208 Wye system 250mcm/250mcm/250mcm/1/0 in a 4" Rigid Metal conduit for a 500 amp service ?
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04-17-2012, 11:02 PM
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#2
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With or without soap?
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04-17-2012, 11:03 PM
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#3
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wo
Quote:
Originally Posted by Ninety
With or without soap?
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Without. Simpull Al
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04-17-2012, 11:10 PM
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#4
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Quote:
Originally Posted by Cletis
Can I put 3 sets (parallel) of 208 Wye system 250mcm/250mcm/250mcm/1/0 in a 4" Rigid Metal conduit for a 500 amp service ?
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500 Amp?
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04-17-2012, 11:36 PM
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#5
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?
Quote:
Originally Posted by Awg-Dawg
500 Amp?
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Yeah. Anything wrong with that? Let's say I had a calculated load of 467 amps
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04-17-2012, 11:38 PM
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#6
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Quote:
Originally Posted by Cletis
Yeah. Anything wrong with that?
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No.
Ive just never seen a 500 amp service. 
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I'm just hoping to not end up on Electricmanscotts signature line.
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04-17-2012, 11:42 PM
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#7
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me
Quote:
Originally Posted by Awg-Dawg
No.
Ive just never seen a 500 amp service. |
I'm a trendsetter..
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04-17-2012, 11:45 PM
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#8
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Quote:
Originally Posted by Cletis
I'm a trendsetter..
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Clearly, that has never been questioned 
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The Following User Says Thank You to Awg-Dawg For This Useful Post:
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04-18-2012, 12:09 AM
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#9
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Quote:
Originally Posted by Cletis
Can I put 3 sets (parallel) of 208 Wye system 250mcm/250mcm/250mcm/1/0 in a 4" Rigid Metal conduit for a 500 amp service ?
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Is this a homework question?
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Last edited by Awg-Dawg; 04-18-2012 at 05:15 AM.
Reason: wrong answer
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04-18-2012, 02:09 AM
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#10
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Quote:
Originally Posted by Cletis
Can I put 3 sets (parallel) of 208 Wye system 250mcm/250mcm/250mcm/1/0 in a 4" Rigid Metal conduit for a 500 amp service ?
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Quote:
Originally Posted by Cletis
Yeah. Anything wrong with that? Let's say I had a calculated load of 467 amps
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If I read your post correctly you will have 9CCC and 3non CCC in one 4" RGS conduit. Thats 12 cables in the one conduit,,,,,,How many guys going to pull the wire and how many are going keep it from getting knotted up?
What is your insulation type?
How long is the run?
Table 310.15(B)(2)(a) Say's 7-9 CCC's you go to a 70% rating.
Assuming an insulation in the 75 degree column your starting at 205 amps.
205amp X .7 = 143.5 amp
143.5 X 3 = 430.5 amp
Really want to do that?
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04-18-2012, 06:56 AM
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#11
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sounds like you might consider 3 parrallel pipe runs Cletis......~CS~
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04-18-2012, 07:14 AM
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#12
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Quote:
Originally Posted by acrwc10
Table 310.15(B)(2)(a) Say's 7-9 CCC's you go to a 70% rating.
Assuming an insulation in the 75 degree column your starting at 205 amps.
205amp X .7 = 143.5 amp
143.5 X 3 =430.5 amp
Really want to do that?
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You would use the 90 column to figure the derating unless the conductors he is using are only 75 which would be odd.
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04-18-2012, 08:22 AM
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#13
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Xhhn-2 al
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04-18-2012, 12:26 PM
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#14
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Quote:
Originally Posted by chicken steve
sounds like you might consider 3 parrallel pipe runs Cletis......~CS~
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Even two runs would be better, I'm still interested in knowing the length of the run. If it's 4 feet horizontal from one panel to another, go for it. If its a real long run, IMHO, it will "F" up the conductors and be a nearly impossible pull. I just watched a "pool guy" pull a 300' run of #2 thwn through an 1-1/4" pvc and he was using a back how because they could not pull it by hand, "PRICELESS'' 
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04-18-2012, 12:33 PM
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#15
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Quote:
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Originally Posted by acrwc10
Even two runs would be better, I'm still interested in knowing the length of the run. If it's 4 feet horizontal from one panel to another, go for it. If its a real long run, IMHO, it will "F" up the conductors and be a nearly impossible pull. I just watched a "pool guy" pull a 300' run of #2 thwn through an 1-1/4" pvc and he was using a back how because they could not pull it by hand, "PRICELESS'' |
12ft
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04-18-2012, 01:03 PM
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#16
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Phosphate Coated
Join Date: Apr 2011
Location: California
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Quote:
Originally Posted by acrwc10
If I read your post correctly you will have 9CCC and 3non CCC in one 4" RGS conduit. Thats 12 cables in the one conduit,,,,,,How many guys going to pull the wire and how many are going keep it from getting knotted up?
What is your insulation type?
How long is the run?
Table 310.15(B)(2)(a) Say's 7-9 CCC's you go to a 70% rating.
Assuming an insulation in the 75 degree column your starting at 205 amps.
205amp X .7 = 143.5 amp
143.5 X 3 =430.5 amp
Really want to do that?
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Don't you mean 310.15(B)( 3)(a) nec 2011 ?
Adjustment factors for more than three conductors in a raceway.
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04-18-2012, 10:01 PM
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#17
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Senior Member
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Location: California SFO bay area
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Quote:
Originally Posted by Cletis
12ft
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12' thats just a long nipple, but it will still be a pain in the butt, I'd run atleast two conduits.
Quote:
Originally Posted by dronai
Don't you mean 310.15(B)(3)(a) nec 2011 ?
Adjustment factors for more than three conductors in a raceway.
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I was in the 08' but it was also late when I posted that.
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