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2500 amp service #216019
09/07/15 08:47 PM
09/07/15 08:47 PM
M
Merlin  Offline OP
Member
Joined: Jan 2004
Posts: 171
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?

Work Gear for Electricians and the Trades
Re: 2500 amp service [Re: Merlin] #216020
09/07/15 08:56 PM
09/07/15 08:56 PM
T
twh  Offline
Member
Joined: Mar 2004
Posts: 940
Regina, Sask.
Aluminum. Then, all sizes are easy.

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

Member
Joined: Apr 2002
Posts: 6,967
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
Re: 2500 amp service [Re: HotLine1] #216042
09/16/15 12:19 AM
09/16/15 12:19 AM
M
Merlin  Offline OP
Member
Joined: Jan 2004
Posts: 171
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

Re: 2500 amp service [Re: Merlin] #216045
09/16/15 11:35 AM
09/16/15 11:35 AM
HotLine1  Offline

Member
Joined: Apr 2002
Posts: 6,967
Brick, NJ USA
Merlin:
I stand corrected....I did not 'see' 2500 amps.



John
Re: 2500 amp service [Re: Merlin] #216073
09/22/15 02:10 AM
09/22/15 02:10 AM
Scott35  Offline

Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,708
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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