ABB SGX-116-1: The High-Performance Signal Converter and Repeater Relay Module

In a water treatment plant’s control panel, a PLC’s 24V DC digital output card needs to start a 240V AC chemical dosing pump motor. Directly connecting the PLC output to the motor contactor coil risks damaging the PLC card from voltage spikes and lacks electrical isolation. This is where the ABB SGX-116-1​ is installed. The PLC’s 24V DC signal energizes the relay coil inside the SGX-116-1, which provides robust galvanic isolation. The relay’s heavy-duty contacts then close to safely switch the 240V AC power to the motor contactor. In this role, the SGX-116-1​ solves the critical pain points of signal level mismatch, provides essential electrical protection for expensive PLC cards, and adds a reliable, repairable switching point to the system.