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2500 amp service #216019 09/07/15 08:47 PM
Joined: Jan 2004
Posts: 171
M
Merlin Offline OP
Member
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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Re: 2500 amp service [Re: Merlin] #216020 09/07/15 08:56 PM
Joined: Mar 2004
Posts: 947
T
twh Offline
Member
Aluminum. Then, all sizes are easy.

Re: 2500 amp service [Re: Merlin] #216021 09/07/15 09:35 PM
Joined: Apr 2002
Posts: 7,237
HotLine1 Offline
Member
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
Re: 2500 amp service [Re: HotLine1] #216042 09/16/15 12:19 AM
Joined: Jan 2004
Posts: 171
M
Merlin Offline OP
Member
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

Re: 2500 amp service [Re: Merlin] #216045 09/16/15 11:35 AM
Joined: Apr 2002
Posts: 7,237
HotLine1 Offline
Member
Merlin:
I stand corrected....I did not 'see' 2500 amps.



John
Re: 2500 amp service [Re: Merlin] #216073 09/22/15 02:10 AM
Joined: Oct 2000
Posts: 2,721
Scott35 Offline
Broom Pusher and
Member
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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