Siemens 3SF7844-8BD24-1SS1 Type 4 Safety Light Curtain, 30 m

The Siemens 3SF7844-8BD24-1SS1 is a Type 4 safety light curtain host receiver from the SIMATIC FS420I family, specified for point-of-operation guarding where a 30 mm resolution catches fingers reaching into the hazard zone (finger-protection class per IEC 61496-1/2). The 1650 mm protected height and 0 to 18 m range cover large access openings on automated assembly or packaging lines. Blanking capability allows fixed or floating objects within the field to pass without tripping the safety output — useful for workpieces or fixtures that must remain in the beam path during normal operation. PROFIsafe bus connection integrates directly into a SIMATIC safety CPU over the standard PROFIBUS or PROFINET cable plant, eliminating a separate safety relay or hardwired OSSD pair. The host receiver pairs with a corresponding transmitter (same resolution and height) to form the light curtain pair; the bus interface handles the safety data telegram (PROFIsafe profile) and diagnostic feedback to the controller.