Our POCOs here require a load calculation of some detail ('ESI') for service installs/upgrades. That results in them providing a service.
Usual or common here for a comm/lite ind is 200 to 400 amp 277/480, 4 wire from a pole mounted set of pots.
Inside is a 277/480 mcb panel at either 200 or 400 amps. From there. dependent on the 120/208 volt loads, a 75 KVA xfr is set 100 amp primary, 200 amp secondary into a 42 circuit space panel.
Without any load info from you, we can only provide 'spec' info.
PS: The secondary (common here) is 120/208 volt, 3 phase, 4 wire...careful if you need 120/240 volt!
