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#177421 - 05/02/08 08:48 AM 2500 KVA 480/277 secondary Transformer conduit & w  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
Michigan
Thur experience for Cost (Material & Labor) what have you found to be the most cost effective combination of pipe & wire??? Pvc Sch. 40 with Alum or Copper . I;m looking for 3000 amps. Another words 500 mcm , 750, 1000 copper or alum.
4 wires in a conduit. Useing 310.16 75C & 110.14c for terms.
Yoopers
Also mostly 480 volt loads so Neutral can be 12 1/2 percent of phase conductors right.


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#177423 - 05/02/08 10:19 AM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: Yoopersup]  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,259
Fullerton, CA USA
Didn't you already ask this question back in February?


#177431 - 05/02/08 01:09 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: electure]  
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
I'd take a look at bus duct for that size feeder.


Don(resqcapt19)

#177438 - 05/02/08 05:56 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: resqcapt19]  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
Michigan
One I posted in Feb was a bit different , Just wondering thur experience which way worked out better.never to proud to learn. Right


#177523 - 05/05/08 08:02 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: Yoopersup]  
Tesla  Offline
Member
Joined: Jun 2004
Posts: 1,273
Sacramento, CA
At 3000 Amps your 'window' becomes restrictive, you'll need to stuff 400 Amps in each of eight pipes. That means that you might be forced to go with copper in schedule 40 PVC.

By comparison, bus duct can be had at 3000 Amps in AL.

The shorter path and cheaper conductor makes bus duct a serious competitor.


Tesla

#177525 - 05/05/08 08:59 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: Tesla]  
ghost307  Offline
Member
Joined: May 2005
Posts: 900
Chicago Illinois USA
Another consideration with bus duct is the difference in labor hours. Slap up 1 10' length of bus duct and you're done with 10' of feed. For 10' of conduit you still have to pull and terminate the wires...PLUS you have multiple sets of everything.


Ghost307

#177571 - 05/07/08 08:01 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: ghost307]  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
Michigan
Cost of Buss Duct custom made otta this world .


#177583 - 05/07/08 11:35 PM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: Yoopersup]  
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,489
Michigan USA
Ernie- You've left out some details (as usual) and I wonder if the question factors in the grounding conductor? With metal raceway - no ground wire- with non-metallic you will need a ground wire- since this is not service. Right? Wrong?


George Little

#177590 - 05/08/08 07:17 AM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: George Little]  
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
How long is the total run? You have to watch out for the length difference with parallel runs.


Don(resqcapt19)

#177594 - 05/08/08 08:52 AM Re: 2500 KVA 480/277 secondary Transformer conduit & w [Re: resqcapt19]  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
Michigan
George
Service conduits from utility Co, transformer to Service gear that means NO GROUND WIRE.
Total run is Aprox. 40feet and yes I know about requrements of Parrell runs.
Buss 90's if you've ever installed then cost a bundle as well as regular buss. But I agree worth a price compaireson.

Last edited by Yoopersup; 05/08/08 08:59 AM.

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