We keeping debating what defines a service entrance per NEC. Take a typical large facility with multiple buildings . We purchase power and then it goes through our transformers, distributed across the facility and more transformers to lower the voltage again. Is the service enterance where we take ownership or the secondary of every transformer?

IMHO, your service entrance is the feeders from your utility voltage transformation (e.g. 13.2kV to 480/277V or similar) to the main switchgear, switchboard, panelboard, etc. of each building.

If you are primary metered and have multiple large transformers for a campus system, then the demarcation point is called the "point of common coupling". This could be a metering cabinet owned by the utility, which then is the origination point of your campus electrical distribution system.

Mike

PS I'm sure there will be a few opinions on this.

I agree. The service begins where the utility feeders end. Stop and think, the utility is not obligated to follow NEC. But your distribution on your campus is.

So the first disconnecting means AFTER the POINT OF SERVICE is your SERVICE DISCONNECT. Main disconnects after the transformers fed by this SERVICE DISCONNECT are not SERVICE DISCONNECTS. Are you interested in identifying the SERVICE DISCONNECTS for grounding purpuses?

Services can be low voltage or high voltage (NEC definition) depending how you obtain your supply from the local utility. At our plant, we receive 115kV service and then transform and distribute within our customer owned distribution system. The NEC handbook has some good explanation of this distinction for campus styled multibuilding complexes in Art 90.2, 225.32, and 695.3 (C). The definition of service has changed over the years and many older engineers and electricians still use the old definitions. I have attached a few docs I developed to help explain services to my workforce. They may be of use to you also.