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#216019 - 09/07/15 05:47 PM 2500 amp service
Merlin Offline
Member

Registered: 01/27/04
Posts: 170
Loc: NW Indiana
Looking for some suggestions.....I am quoting a job to install a 2500 amp, 480/277V service. This will be feed from a pad mount transformer about 30 feet into a building. Obviously it will be parallel conductor fed. What combination would you all use? 750kcmil, 1000kcmil,.....any thoughts?

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#216020 - 09/07/15 05:56 PM Re: 2500 amp service [Re: Merlin]
twh Offline
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Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
Aluminum. Then, all sizes are easy.

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#216021 - 09/07/15 06:35 PM Re: 2500 amp service [Re: Merlin]
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6785
Loc: Brick, NJ USA
Merlin:

Common is 6 sets of 600 KCMil Cu THHN/THWN in 4" PVC

You have to check the secondary 'window' of the pad mount xfr., as that limits the quantity of conduits you can install.
_________________________
John

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#216042 - 09/15/15 09:19 PM Re: 2500 amp service [Re: HotLine1]
Merlin Offline
Member

Registered: 01/27/04
Posts: 170
Loc: NW Indiana
Correct me if I'm wrong, but 6-600's would be
6 x 475 = 2850.
Derated for 4 conductors in conduit(480/277) at 80%
2850 x .8 = 2280.

Wouldn't it be 6x750kcmil?
6 x 535 = 3210
3210 x .8 = 2568

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#216045 - 09/16/15 08:35 AM Re: 2500 amp service [Re: Merlin]
HotLine1 Offline

Member

Registered: 04/03/02
Posts: 6785
Loc: Brick, NJ USA
Merlin:
I stand corrected....I did not 'see' 2500 amps.
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John

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#216073 - 09/21/15 11:10 PM Re: 2500 amp service [Re: Merlin]
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
If this Installation is for Service Feeders (from a Poco Transformer to Service Equipment), you need to verify the requirements with the Service Planner before bidding this Project (or before commencing the actual work!)

If the Installation is on the LOAD side of the Service Disconnect, then (6) 4" Ducts with 4-750MCM CU. per duct is sufficient... if NO Equipment Grounding Conductors are installed!

If an EGC is to be installed, that will be a minimum of (1) 350MCM CU. per duct, so now the Ducts would be 5" (???)
dunno

--Scott (EE)
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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