The Siemens 3SF7844-8MB26-0SS1 is a Type 4 safety light curtain receiver from the SIMATIC FS450I series, with a 14 mm resolution and 1800 mm protective height. It connects via PROFIsafe bus and includes muting capability for material handling pass-through. The 14 mm finger-protection resolution means it catches hands or fingers reaching into the hazard zone — that's finger-protection class per IEC 61496-1, not just hand detection. The 1800 mm height covers a full standing access area, so it suits large machine guarding or robotic cell perimeters. The muting function lets pallets or workpieces pass through without tripping the safety output, which keeps production moving on conveyor lines.
The 14 mm resolution is the key selection parameter: it determines the smallest object the curtain detects. At 14 mm, it catches individual fingers (finger protection), which is required for applications where operators can reach past the light curtain into the danger zone. The 1800 mm height covers the full vertical opening of a typical machine guard. The PROFIsafe bus connection integrates directly into a Siemens safety CPU (like an F-CPU or ET 200SP F) without a separate safety relay — the safety signal travels over the same PROFIBUS or PROFINET cable as standard I/O, which saves cabinet space and wiring. The muting function uses external sensors to temporarily bypass the curtain when a workpiece or pallet passes through, then re-enables it — essential for automated material handling where you cannot stop the line for every part.
Deployment context
This light curtain is built for guarding hazard zones on automated machinery — press brakes, robotic cells, packaging lines, assembly stations. The Type 4 classification (per IEC 61496-1) means it meets the highest safety integrity level for electro-sensitive protective equipment, suitable for applications up to SIL 3 / PL e. The PROFIsafe interface eliminates the need for a separate safety relay module, which simplifies the safety circuit and reduces wiring. The muting capability makes it a fit for conveyor pass-through points where parts must enter and exit the guarded area without stopping the line.