Safety light curtain receiver for guarded zones
The Siemens 3SF7844-8BB13-0SS1 is a Type 4 safety light curtain receiver from the SIMATIC FS420I family, designed for use with a matching emitter to create an electro-sensitive protective device (ESPE) per IEC 61496-1/2. Its 14 mm resolution means it detects fingers reaching into a hazard zone — finger-protection class — and the 900 mm protected height covers a typical machine access opening. The 0 to 6 m operating range gives flexibility for guarding larger cells or walk-up areas. This receiver integrates via PROFIsafe bus connection, so it talks directly to a F-CPU over PROFINET without a separate safety relay. The blanking function (fixed or floating) lets you ignore stationary objects like a workpiece fixture within the field, while the Type 4 architecture ensures a single failure does not lead to loss of the safety function.
This is the receiver unit only; it requires a matching Type 4 emitter from the same FS420I family to form a complete light curtain. Mounting brackets and alignment aids are ordered separately. The PROFIsafe bus connection uses a standard M12 connector, so the field wiring is a single cable back to the switch or IO-Link master.