Last edit: 11/08/2023
In Category 2, both Basic and Well-tried safety principles must be followed.
It is a single channel architecture with the monitoring of each subsystem done, in its most general form, by an external unit called Test Equipment. In case a fault is detected, the TE signals it to the “outside world” thanks to an output: the OTE.
Hereafter how the Safety-related block diagram looks like.