The trade term is unfused servce conductors. Unfused as no ocpd on secondary of poco transformer. The unfused conductors are protected 3 ways;
1. Limit on length inside building
2. Type of wiring method
3. Special rules for grounding
Here is a concept to think about
Unfused wires are protected against overload (load calculation) but not short circuits or ground faults.
In WA, we can have 15ft of raceway, only certain types, in the building for unfused conductors. No SE cable or emt.
Can run SE cable outside but not in.
I have never in 40 years seen SE cable used for a service.
For the OP, its important you understand the why on these rules, the how is in the NEC.