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	Subject - Wire Size David Hyatt On a 200 amp service in a office building, what size Al wire can be used from the meter to panel? 4/0? Type USE-2. It falls into the 90* column but the panel, is it rated at 90*? If I have to use the 75* column I am up to a 250 MCM. I would use copper but money is tight. Ryan_J Hi David. You can't use the 90 degree column because of 110.14. Also, when you are doing commercial, it is important to remember that feeder/service conductors are sized differently, so make sure you use 310.16, not 310.15(B)(6). If the load is less than 180 amps (and it probably is), you may use 4/0 aluminum and apply the allowance of 240.4(B) to jack it up to 200 amps. David Hyatt Yep that good Ryan, probably pulling only 100 amps. That is why the building next door had 4/0 AL. I didn't do a calculation, I did use TBL 310.16, I forgot about 240.4B next higher size breaker. All the building has is 38 REC. about 10 switches, 25 lights, and a gas heat and electrical air @30 amps. Ryan_J Never forget 240.4(B) my freind. Lots of money to be saved there :) I'm glad I could help, and good luck. Pierre Belarge Don't forget 240.4(C) - lots of money to be lost there Pierre Ryan_J Ain't that the truth! Removing 3 sets of 500's for a 1200 amp service pretty much sucks.