{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SM3646-8KK12","brand":"Siemens","brandSlug":"siemens","productSlug":"5SM3646-8KK12","canonicalUrl":"https://aoctrl.com/siemens/5SM3646-8KK12","factsUrl":"https://aoctrl.com/api/mcp/products/5SM3646-8KK12","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SM3646-8KK12, 4-pole RCCB, Type A selective, 63 A, 300 mA, 400 V AC, SIGRES variant for harsh ambient conditions.","salesMarkdown":"The Siemens 5SM3646-8KK12 is a 4-pole residual current operated circuit breaker (RCCB) from the SENTRON 5SM3 series, designed as a Type A selective device with a rated tripping residual current of 300 mA and a rated current of 63 A at 400 V AC. The selective design (short-time delayed) means it coordinates with downstream RCCBs — it holds during a fault long enough for the downstream device to clear, isolating only the faulty branch. This avoids a full-panel blackout on a single branch fault. Rated at 63 A continuous and 300 mA trip threshold: this is a feeder or submain RCCB, not a final-circuit device. The 300 mA threshold provides earth-leakage protection while tolerating the natural leakage of long cable runs and multiple connected loads. Rated impulse withstand current of 1 kA (surge current resistance) means it survives the inrush from capacitor banks or nearby lightning-induced surges without nuisance tripping — important for industrial panels with power-factor correction or long overhead supply lines. Mechanical service life of 10 000 switching cycles typical — adequate for a protective device that operates infrequently; not a switching contactor for daily cycling. Mounting position any orientation, installation depth 70 mm. Terminals accept solid or stranded copper from 1.5 mm² up to 25 mm², with a tightening torque of 2.5 to 3 N·m. This is the SIGRES variant, specified for harsh ambient conditions — the standard 5SM3 RCCB without the SIGRES suffix is the standard-duty version. The SIGRES designation means the internal components and housing are selected for higher resistance to humidity, temperature cycling, and corrosive atmospheres, per the manufacturer's SIGRES specification.","metaTitle":"Siemens 5SM3646-8KK12 SENTRON RCCB, 63A, 300mA, 4P, Type A S","metaDescription":"Siemens 5SM3646-8KK12 SENTRON RCCB, 4-pole, Type A selective, 63 A rated current, 300 mA trip, 400 V AC. Active 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":"77 mm","Solid":"1.5 ... 25 mm²","Width":"72 mm","Height":"90 mm","Stranded":"1.5 ... 25 mm²","Rated Value":"50 Hz","Mounting type":"DIN rail (REG)","During Storage":"-40 ... +75 °C","Number of poles":"4","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Product variations":"SIGRES (harsh ambient conditions)","Ambient temperature":"-25 ... +45 °C","Operating frequency":"50Hz","Product designation":"RCCB","Protection class IP":"IP20, if the distribution board is installed, with connected conductors","Overvoltage category":"III","Design of the product":"Selective","Number of width units":"4","Type of fault current":"A","acc. to DIN EN 61346-2":"F","acc. to DIN EN 81346-2":"F","circuit-breaker / Design":"5SM3","Current / at AC / rated value":"63 A","Product feature / silicon-free":"Yes","Position / of power supply cord":"bottom","Protection against electrical shock":"Finger and back-of-hand safe","Supply voltage / at AC / rated value":"400 V","Surge current resistance / rated value":"1 kA","Switching function / short-term delayed":"No","Tripping residual current / rated value":"300 mA","Tightening torque / with screw-type terminals":"2.5 ... 3 N·m","Size of installation devices / acc. to DIN 43880":"1","Supply voltage / for testing equipment / minimum":"100 V","Mechanical service life (switching cycles) / typical":"10 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$561.48","priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=370156&mlfb=5SM3646-8KK12","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SM3646-8KK12/alternatives.json"},"ai":{"faq":[{"question":"What is the difference between this and a standard 5SM3 RCCB?","answer":"The 5SM3646-8KK12 is the SIGRES variant, designed for harsh ambient conditions with enhanced resistance to humidity, temperature cycling, and corrosive atmospheres. The standard 5SM3 RCCB without the SIGRES suffix is for normal indoor environments."},{"question":"What conductor sizes does the 5SM3646-8KK12 accept?","answer":"The terminals accept solid or stranded copper from 1.5 mm² up to 25 mm², with a tightening torque of 2.5 to 3 N·m."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SM3646-8KK12","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/5SM3646-8KK12 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}}