Type 4 receiver with blanking and Profisafe integration
The Siemens 3SF7844-8BD22-0SS1 is a Type 4 safety light curtain receiver from the SIMATIC FS420I series, rated for finger and hand detection with a 30 mm resolution over a 1500 mm protected height. The blanking function allows fixed or floating objects within the field to be masked, so the curtain guards the hazard zone without nuisance tripping on workpiece or fixture protrusions. Profisafe bus connection means it integrates directly into a safety-rated PROFINET network, eliminating the need for a separate safety relay or interface module in most Siemens-based safety architectures.
Deployment context
The 0 to 18 m operating range suits it for guarding large press brakes, robotic cells, or conveyor in-feed zones where the transmitter and receiver are mounted several meters apart. The Type 4 classification (SIL 3, PL e per IEC 61496-1) means it is certified for use in safety circuits where a failure must not lead to loss of the safety function.