{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SM9643-0","brand":"Siemens","brandSlug":"siemens","productSlug":"5SM9643-0","canonicalUrl":"https://aoctrl.com/siemens/5SM9643-0","factsUrl":"https://aoctrl.com/api/mcp/products/5SM9643-0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON RC unit electronic for 5SL4, 4-pole, type AC, In: 40 A, 300 mA, Un AC: 400 V, order code 5SM9643-0.","salesMarkdown":"This is the companion unit for the 5SL4 line, not a standalone device; you bolt it above the MCB on the rail, and the top-side supply feeds through the RC unit first. The 300 mA trip threshold is the key spec for this part — that's not a personnel-protection level (those are 10 or 30 mA); it's an equipment-protection / fire-prevention level, typically used on circuits where nuisance tripping from leakage in long cable runs or industrial gear would take down a 30 mA RCD. The 3 kA surge current resistance means it'll survive lightning-induced or switching transients up to that peak without damage. Mounting is standard DIN rail (EN 60715) — three modular width units wide (54 mm), 70 mm deep, 100 mm tall. The position on the rail is top-side, above the miniature circuit breaker, with supply coming in from above. Any mounting position works. The 10 000 mechanical switching cycles typical service life is fine for a distribution-board device that sees infrequent manual operation or fault clearing; it's not a contactor-duty part.","metaTitle":"Siemens SENTRON 5SM9643-0 RC Unit, 40 A, 300 mA, 4P","metaDescription":"Siemens SENTRON 5SM9643-0 RC unit for 5SL4. 4-pole, type AC, 40 A rated, 300 mA trip, 400 V. DIN rail mount. Current production. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Residual Current Breakers (RCCB/RCBO)"],"specifications":{"Depth":"70 mm","Width":"54 mm","Height":"100 mm","Maximum":"55 °C","Minimum":"-25 °C","Rated Value":"50 Hz","Number Of Poles":"4","lifecycle_stage":"current","Fastening Method":"Standard rail mounting","Mounting Position":"any","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Product Variations":"DI unit, type AC, 0.3...40 A, 4P, 300 mA","Maximum Permissible":"75 °C","Minimum Permissible":"-40 °C","Product Designation":"RC unit electronic for 5SL4","acc. to IEC 81346-2":"F","protection class IP":"IP20, if the distribution board is installed, with connected conductors","Overvoltage Category":"III","Design Of The Product":"Instantaneous","Residual Current Type":"AC","acc. to DIN EN 61346-2":"F","Number Of Modular Width Units":"3","Product Feature / Silicon-Free":"Yes","acc. to EN 60898 / rated value":"6 kA","Position / Of Power Supply Cord":"Top, above miniature circuit breaker","Tripping Fault Current / Rated Value":"300 mA","supply voltage / at AC / rated value":"230/400 V","Surge Current Resistance / Rated Value":"3 kA","according to IEC 61008-1 / rated value":"6 kA","Switching Function / Short-Term Delayed":"No","operational current / at AC / rated value":"40 A","Supply Voltage / For Testing Equipment / Minimum":"125 V","size of installation devices / acc. to DIN 43880":"1","Mechanical Service Life (Switching Cycles) / Typical":"10 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/c92d17de8bdbe43f3da3de165a366346.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=629214&mlfb=5SM9643-0","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SM9643-0/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 5SM9643-0 and how do I get a price?","answer":"The 5SM9643-0 is sourced and quoted to order through independent distribution against an RFQ. Availability and current pricing are confirmed at quote time; send an RFQ to initiate a procurement quote."},{"question":"What is 5SM9643-0's listed depth?","answer":"The installation depth is 70 mm, matching the overall depth of 70 mm. The width is 54 mm (3 modular units), height 100 mm."},{"question":"What compliance documentation does this brand provide for 5SM9643-0?","answer":"As a current-production Siemens SENTRON component, standard documentation includes the manufacturer's declaration of conformity to IEC 61008-1 and EN 60898, CE marking, and UKCA. RoHS and REACH compliance is standard for this product line. Specific certificates are available on request with an RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SM9643-0","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/5SM9643-0 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}}