Jed54 said:
This same home has a 200 amp main service panel with No Main Breaker.. I would assume its wired to main lug. Since no main breaker is present does the power have to be disconnected at meter to add a main?
It is customary but not required to have a single Main Circuit Breaker.
230.70 Requires a means to disconnect all conductors in a building from the service-entrance conductors.
230.71 Requires that there be not more than six switches or circuit breakers, grouped together, to meet the requirement of 230.70.
It would be permissible put not more than six two-pole breakers in the Main Lug panel to serve sub-panels at various points in the house.
It would be better to install a single main breaker to disconnect all of the service conductors.
It is sometimes possible to convert the Main Lug configuration to a Main Breaker panel.
See 230.90 Exception 3 regarding the capacity of the 2 to 6 circuit breakers providing protection to the Service conductors.