SST Communication Interface Card for EtherCAT (SST-ESR2-CLX-RLL)

The SST-ESR2-CLX-RLL (Molex part 112073-0001) is an SST communication module for Rockwell Automation ControlLogix chassis, originally from Woodhead Industries and now Molex. It provides one RJ45 Ethernet port running Modbus TCP as client and server simultaneously, and two 9-pin D-sub serial ports configurable for RS-232 or RS-485 running Modbus RTU or ASCII as master and/or slave. The module exchanges data directly with the ControlLogix processor’s tags as an I/O module, so no ladder logic message instructions are needed, and it can act as a gateway, for example reading serial Modbus slaves and serving the data over Modbus TCP, using a 32k-word and 32k-bit internal database. Configuration is done with the SST Console software, and the RLL support allows remote monitoring and download of configuration through the ControlLogix network; configurations can also be loaded from a USB memory stick. Molex lists an MTBF of 56 years. Despite the name in the source list, it does not support EtherCAT; it is used to integrate Modbus meters, drives, PLCs and instruments into ControlLogix systems.