ABB 1SAP210600R0001 - TU551-CS31 Interface Terminal Unit (AC500 S500)

The ABB 1SAP210600R0001 is the order code for the TU551-CS31 interface terminal unit of the AC500 S500 I/O family: a screw-terminal base unit for CS31 bus configurations with 24 VDC supply, described in distributor listings as an interface terminal unit for CS31 protocol systems. Listings across independent stores and marketplaces show consistent identities, including new-in-box units, and refurbished stock is offered by specialists with warranty. The TU551-CS31 serves as the bus-coupling base for S500 I/O assemblies communicating over CS31; the spring-terminal counterpart is TU552-CS31 (1SAP210400R0001). Confirm terminal style before ordering.