The ABB 1SAP311300R0278 TB5610 terminal base is the comms hub for an AC500 V3 system – one slot that takes a communication module and gives you 2 Ethernet, 1 serial, and 1 CAN interface on a single base. That means you can wire the CPU to a fieldbus, a local HMI serial link, and a CAN daisy chain without stacking multiple expansion modules.
Integration notes for the line-side engineer
DC input, IP20 enclosure. Serial and CAN ports share the same base footprint. 2 Ethernet interfaces, 1 serial interface, 1 CAN interface on one base.