When a link is created between a harness and an object of a terminal block grouping,
this is the topmost grouping object which is allocated to the harness content. This way, all the objects from the terminal block grouping are linked to the harness.
Note:
If the harness link operation is done before the terminal block grouping definition, additional checks are done during the terminal block grouping operation to manage the links between the objects and the harness.
Harness Link Review
The Electrical: Harness Links Review B.I checks every terminal block of the grouping. If the topmost grouping terminal block is allocated to a harness, all the children objects are considered as allocated to the harness and are highlighted in green.