{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3SF7844-8MS51-0SS1","brand":"Siemens","brandSlug":"siemens","productSlug":"3SF7844-8MS51-0SS1","canonicalUrl":"https://aoctrl.com/siemens/3SF7844-8MS51-0SS1","factsUrl":"https://aoctrl.com/api/mcp/products/3SF7844-8MS51-0SS1","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 3SF7844-8MS51-0SS1, Type 4 standard receiver for light grid, 500 mm height, 500 mm width, muting, 6 to 70 m range, PROFIsafe bus connection, SIMATIC FS420i.","salesMarkdown":"The Siemens 3SF7844-8MS51-0SS1 is a Type 4 standard receiver for a safety light grid, part of the SIMATIC FS420i family. It provides a 500 mm protective height and a detection range from 6 to 70 m, with integrated muting capability. The PROFIsafe bus connection allows direct integration into a safety-rated PROFINET network without a separate safety relay. Type 4 per IEC 61496-1/2 means this receiver is rated for the highest level of fault tolerance in optoelectronic protective devices — it can detect a single component failure and still maintain a safe state. The 500 mm protective height defines the vertical zone it monitors; paired with a matching transmitter, it creates a curtain that guards access to a hazard area. The 6 to 70 m range covers most conveyor, press, and robotic cell applications; the lower end (6 m) is the minimum separation between transmitter and receiver, not a resolution figure. Muting built into the receiver means it can temporarily bypass the light grid for material transport (e.g., a pallet passing through) without external muting sensors or a separate controller — the logic is handled inside the FS420i system over PROFIsafe. This simplifies wiring and reduces the component count in the safety circuit. ## Deployment context Mounts in a standard industrial enclosure with the transmitter opposite, aligned within the manufacturer's specified beam angle. The PROFIsafe connection means it communicates safety status directly to a failsafe PLC (e.g., SIMATIC S7-1200/1500 F-CPU) over the same Ethernet cable as standard I/O — no dedicated safety bus coupler needed. The 500 mm height suits guarding of a typical conveyor infeed or machine access point where a full-height light curtain would be overkill.","metaTitle":"Siemens 3SF7844-8MS51-0SS1 Safety Light Grid Receiver, Type","metaDescription":"Siemens 3SF7844-8MS51-0SS1 Type 4 standard receiver for light grid, 500 mm height, 6–70 m range, muting, PROFIsafe via SIMATIC FS420i. Current lifecycle stage. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Safety Interlock Switches"],"specifications":{"lifecycle_stage":"current"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/3SF7844-8MS51-0SS1/alternatives.json"},"ai":{"faq":[{"question":"What is the detection range of this light grid receiver?","answer":"The receiver operates over a range of 6 to 70 m, paired with a matching Type 4 transmitter."},{"question":"What does the muting function mean on this part?","answer":"Muting allows the light grid to be temporarily bypassed for material transport (e.g., a pallet passing through) without external muting sensors — the logic is handled internally over the PROFIsafe bus connection."},{"question":"Where can I buy 3SF7844-8MS51-0SS1 and how is it quoted?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3SF7844-8MS51-0SS1","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3SF7844-8MS51-0SS1 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}