The Siemens 3SF1324-1SD21-1BA1 is a SIRIUS safety position switch with tumbler, designed for positive-opening switching in guard-door and hazard-zone applications. The 1300 N locking force holds the guard closed against forced entry, and the positive-opening NC contacts (per IEC 60947-5-1) guarantee a break even if the contacts weld — no reliance on spring return alone. The IP66/IP67 plastic enclosure stands up to washdown environments, and the fixed M12 plug (4-pole, ASI+ on pin 1, ASI- on pin 3) integrates directly into an AS-Interface safety network without a separate gateway module.
Mounting position is any orientation, with screw fixing to the machine frame or guard. The separate actuator (3SE5000-0AV0, ordered separately) can approach from five directions, giving layout flexibility on hinged or sliding guards. The M12 plug is fixed — no field-wiring of the switch body; pre-terminated cables or field-attachable connectors mate to the 4-pin interface.