The Siemens 3SF7844-8BD06-1SS1 is a Type 4 safety light curtain host receiver from the SIMATIC FS420I family, rated for finger and hand detection at 30 mm resolution across a 450 mm protected height and a 0 to 18 m operating range. The PROFIsafe bus connection integrates directly into a safety-rated PROFINET network, eliminating the need for a separate safety relay module in the control cabinet.
What the ratings mean for fit
Type 4 per IEC 61496-1/2 is the highest safety integrity for electro-sensitive protective equipment — it can be used for applications up to SIL 3 / PL e without additional guarding. The 30 mm resolution catches fingers reaching into the hazard zone (finger-protection class). The 450 mm protected height and 0–18 m range suit medium-width access points on assembly lines, packaging machines, or robotic cells. PROFIsafe (PROFIsafe bus connection) means the light curtain communicates safety status directly over the standard PROFINET cable, using the black/red RJ45 connector. No hardwired safety relay or dual-channel wiring to a failsafe PLC input is required — the safety function is handled in the PLC's F-host via the GSDML file. This reduces panel wiring and simplifies diagnostics.
Sourcing and lifecycle
For a BOM line that requires this exact host receiver, the part is sourced and quoted to order against an RFQ. Availability and current pricing are confirmed at quote time through independent distribution channels.