Siemens 3TH4346-0BB4 Relay

Siemens 3TH4346-0BB4 is a 73E auxiliary contactor (Hilfsschütz) in the SIRIUS 3TH4 family, delivering a compact 1U high block with ten contacts: 7 normally open (NO) and 3 normally closed (NC), designed for DC operation with a 24 V DC coil. The unit uses screw terminals for DC connections and is intended for control circuits to extend the contact capacity of a main relay or contactor, providing multiple feedback paths and interlocking signals in automation panels. Retail listings describe contacts rated to switch up to 10 A at 24 V DC, making it suitable for low‑power control circuits and signaling tasks in industrial controls; the device is compatible with EN 50011 (73E) and carries Siemens part number 3TH4346-0BB4. As a 1U auxiliary block, it is designed to be mounted alongside the 3TH4 main relays to expand control logic, enabling PLCs and other controllers to monitor auxiliary conditions, implement interlocks, and drive indicator circuits without altering the main switching device. This part is commonly found in PLC‑controlled machines, automated lines, and control panels where additional NO/NC contacts are required for sequencing, safety logic, and feedback loops.