ABB 620 Series Manual page 24

Section 3
Vendor-specific implementation
18
BOS points exist only if the corresponding CROB point has been inserted in the active
point list.
Class assignment cannot be performed on CROBs. They can only be performed on the
corresponding BOS points in a limited fashion; they may only be assigned Class 0 or None
and only affect the class 0 scan. This means they cannot be configured to generate events.
The BOS points, however, have been made available as BI points, which can be
configured to generate events.
1MAC459571-IB C
620 series ANSI
Communication Protocol Manual