{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3SF7844-8MD04-0SS1","brand":"Siemens","brandSlug":"siemens","productSlug":"3SF7844-8MD04-0SS1","canonicalUrl":"https://aoctrl.com/siemens/3SF7844-8MD04-0SS1","factsUrl":"https://aoctrl.com/api/mcp/products/3SF7844-8MD04-0SS1","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIMATIC FS420I, Type 4 safety light curtain receiver, 30 mm resolution, 300 mm protected height, muting, 0-18 m range, PROFIsafe bus connection, order code 3SF7844-8MD04-0SS1.","salesMarkdown":"## What this receiver does in the safety loop The 3SF7844-8MD04-0SS1 is the receiver half of a Type 4 safety light curtain from the SIMATIC FS420I family, paired with a matching emitter to create a guarded zone. 30 mm resolution means it detects fingers and hands reaching past the plane — finger-protection class per IEC 61496-1. The 300 mm protected height covers a compact opening or conveyor infeed, and the 0 to 18 m range gives flexibility for longer spans in a single pair. Muting is built in, so the curtain can be temporarily overridden for material passage without stopping the machine — typical on palletizers or transfer stations where product breaks the beam during normal flow. PROFIsafe bus connection ties directly into a SIMATIC safety controller, eliminating hardwired OSSD pairs and reducing panel wiring. ## Deployment context Mounts in a standard safety light curtain column set or machine frame. PROFIsafe bus connection means the receiver communicates over a shielded M12 or RJ45 cable back to the safety CPU — no separate safety relay needed. The 30 mm resolution and muting function suit guarding zones where product must pass through without a stop signal, such as automated assembly cells or packaging lines.","metaTitle":"Siemens 3SF7844-8MD04-0SS1 Type 4 Safety Light Curtain Recei","metaDescription":"Siemens 3SF7844-8MD04-0SS1 Type 4 safety light curtain receiver, 30 mm resolution, 300 mm height, 0-18 m range, muting, PROFIsafe. Current lifecycle stage. Quoted on request.","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/3SF7844-8MD04-0SS1/alternatives.json"},"ai":{"faq":[{"question":"What is the resolution and range of this light curtain receiver?","answer":"30 mm resolution for finger detection, 300 mm protected height, and a 0 to 18 m operating range per the Siemens spec."},{"question":"Does this receiver support muting?","answer":"Yes, muting is integrated into the receiver — it allows the safety curtain to be overridden during material transport without stopping the machine."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3SF7844-8MD04-0SS1","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/3SF7844-8MD04-0SS1 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}}