The required size of a conduit raceway for a 3-5000 mcm wire is 300 kcmil. It maximizes the limits on the wire fill for raceways.
Using the AWG for wire sizes only goes up to 4/0. After that the increases use MCM to size the wire. So your 262 MCM wire size will be same in AWG. There is no 262 MCM in the North American market place. It goes in 50 MCM increments starting at 250 MCM , 300 MCM, 350 MCM, 400 MCM right up to 2000 MCM cable.
250 mcm
This size service can be wired in a few combinations. Two parallel runs of 1250 MCM, three parallel runs of 600 MCM, four parallel runs of 350 MCM. Of the three choices the four runs of 350 MCM wires would be the easiest to handle if there are any bends in the service entrance conduit.
There are different combination to obtain a current capacity of 1250 amps. A parallel run of #1250 MCM wires. A triple run of #600 MCM wire. The most flexible run would be with a quad run of #350 MCM wire.
500 mcm
The required size of a conduit raceway for a 3-5000 mcm wire is 300 kcmil. It maximizes the limits on the wire fill for raceways.
Using the AWG for wire sizes only goes up to 4/0. After that the increases use MCM to size the wire. So your 262 MCM wire size will be same in AWG. There is no 262 MCM in the North American market place. It goes in 50 MCM increments starting at 250 MCM , 300 MCM, 350 MCM, 400 MCM right up to 2000 MCM cable.
000 <<>> A 750 MCM copper conductor with an insulation factor of 90 degrees C is rated at 500 amps.
500 MCM can carry 380 Amps at 75 degrees C.
2.2 lbs per ft
Ground is sized based on the size of the feeder wire and not the amps of the service! However, for a 600 amp service 1500MCM copper wire is one option (NEC 310.16) ;therefor, ground wire is 3/O copper (NEC 250.66) or another option is a two sets of 350 MCM copper wire then a #2 copper (since the biggest feeder wire is 350MCM).
250 mcm
4 sets of 750 mcm aluminum. Or four parallel runs of 600 MCM copper.
A 750 MCM wire with an insulation factor of 90 degrees C is rated at 500 amps. De rated to 80% will allow 400 amps on the wire. A 900 MCM wire with an insulation factor of 75 degrees C is rated at 520 amps. A 1500 MCM wire with an insulation factor of 60 degrees C is rated at 520 amps. Parallel 250 MCM will give you the same usage. A 250 MCM wire with an insulation factor of 75 or 90 degrees C are rated at 255 and 265 respectively. 255 x 2 = 510 x 80% = 408 amps. 265 x 2 = 530 x 80% = 424 amps.
This size service can be wired in a few combinations. Two parallel runs of 1250 MCM, three parallel runs of 600 MCM, four parallel runs of 350 MCM. Of the three choices the four runs of 350 MCM wires would be the easiest to handle if there are any bends in the service entrance conduit.
A 228 sq mm conductor equates to 450 MCM. A conductor of 450 MCM is not a standard AWG wire size. A standard 400 MCM will carry 380 amps. A standard 500 MCM will carry 430 amps. Difference between 400 and 500 MCM amperage's is 50 amps. Transposing between the two amperage's of 50 amps will be 380 + 25 = 405 or 430 - 25 = 405 amps. This is a very rough calculated answer for the question.