ABB FI820F 3BDH000031R1 

APBU Type of optical branching unit used for connecting parallelconnectedConverter modules to the RDCU.

DSSB Diode Supply System BoardDSU Diode Supply UnitFrame (size) Relates to the construction type of the component in question. forExample, several drive types with different power ratings may havethe same basic construction, and this term is used in reference to allthose drive types.with the ACS800-07 (> 500 kW), the frame size of the driveIndicates the quantity and frame size of the supply modules, plus theQuantity and frame size of the inverter modules, e.g. " 2D4 + 4R8i".to determine the frame size of a drive type, see the rating tables