Siemens 3RA1931-1A Link Module S2 AC

Siemens 3RA1931-1A Link Module S2 AC is a Sirius electrical/mechanical link accessory designed for the 3RV1.31/3RT1.3 motor starters and the 3RW3 family, enabling compact, synchronized operation in AC control circuits. It supports AC operation (S2) and is specified for use with 3RV1.31, 3RT1.3, and 3RW3 devices, making it a key component in multi-device starter assemblies where precise interlock and signaling between the main contactor and protective elements are required. The module's footprint is around 52 mm high by 51.5 mm wide by 58 mm deep, reflecting a compact form factor suitable for tight panel layouts. The 3RA1931-1A variant is part of Siemens' Sirius portfolio, and it is commonly found in applications such as conveyors, pumps, and fans that employ Sirius 3RV/3RT/3RW starters.