{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3SF7844-8TB04-1SS1","brand":"Siemens","brandSlug":"siemens","productSlug":"3SF7844-8TB04-1SS1","canonicalUrl":"https://aoctrl.com/siemens/3SF7844-8TB04-1SS1","factsUrl":"https://aoctrl.com/api/mcp/products/3SF7844-8TB04-1SS1","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIMATIC FS420I Type 4 safety light curtain host receiver, 14 mm finger protection, 300 mm height, 0 to 6 m range, PROFIsafe bus connection, order code 3SF7844-8TB04-1SS1.","salesMarkdown":"## Safety Light Curtain Type 4 Host Receiver — 14 mm, 300 mm, PROFIsafe The Siemens 3SF7844-8TB04-1SS1 is a Type 4 safety light curtain host receiver from the SIMATIC FS420I series. The PROFIsafe bus connection integrates directly into a safety-oriented automation network — no separate safety relay needed for the bus interface. Type 4 per IEC 61496-1/2 is the highest category for electro-sensitive protective equipment: it can tolerate a single fault without losing the safety function. The 14 mm resolution means it detects fingers reaching into the hazard zone (finger-protection class), so it suits press brakes, assembly stations, and robotic cells where hand access must be caught. ## Deployment Context — PROFIsafe Integration This receiver is the host unit in a Type 4 light curtain pair; it processes the emitter beam pattern and communicates the safety status over PROFIsafe. The 0 to 6 m range covers typical guarding distances for medium-sized machinery. Cycle control is built in — the receiver handles the restart interlock and blanking logic internally, reducing PLC safety-program complexity. Mount the receiver and its paired emitter on the machine frame or guarding stanchions. The 300 mm height covers a vertical zone that matches common panel openings or machine apertures. No separate bus coupler is required — the PROFIsafe connection is integral, saving a slot in the safety I/O rack.","metaTitle":"Siemens 3SF7844-8TB04-1SS1 Safety Light Curtain, Type 4, 14","metaDescription":"Siemens 3SF7844-8TB04-1SS1 Type 4 safety light curtain host receiver. 14 mm resolution, 300 mm height, 0-6 m range, PROFIsafe. Current lifecycle. 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/3SF7844-8TB04-1SS1/alternatives.json"},"ai":{"faq":[{"question":"What is the 3SF7844-8TB04-1SS1 used for?","answer":"It is a Type 4 safety light curtain host receiver that guards hazardous machinery by detecting fingers (14 mm resolution) across a 300 mm height and up to 6 m range. It connects directly to a PROFIsafe safety bus, eliminating the need for a separate safety relay module."},{"question":"Where can I buy the 3SF7844-8TB04-1SS1?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Pricing and lead time are confirmed at quote time to match your delivery schedule."},{"question":"What does Type 4 mean for this light curtain?","answer":"Type 4 is the highest safety integrity level per IEC 61496-1 for electro-sensitive protective equipment. It tolerates a single fault without losing the safety function, so it is suitable for applications requiring SIL 3 or PL e per EN 62061 / EN ISO 13849-1."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3SF7844-8TB04-1SS1","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/3SF7844-8TB04-1SS1 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}}