{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SM1646-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SM1646-8","canonicalUrl":"https://aoctrl.com/siemens/5SM1646-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SM1646-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON, selective RCCB, 5SM1646-8, 4-pole, 63 A (40 °C), 300 mA Type A, 10 kA SCCR, DIN rail (REG).","salesMarkdown":"## Selective RCCB for feeder protection — 63 A, 300 mA, Type A The Siemens 5SM1646-8 is a 4-pole selective RCCB from the SENTRON series, rated 63 A at 40 °C and 300 mA residual trip current, Type A. Selective design means it incorporates a short time delay so that downstream RCCBs trip first during a ground fault — only if the fault persists does this unit open, keeping upstream feeders live for the rest of the panel. That coordination is critical in a distribution board feeding multiple sub-circuits: you don't want a single branch fault blacking out the whole board. Rated 400 V AC, 50 Hz, with a short-circuit current rating of 10 kA per IEC 61008-1 and 0.8 kA per EN 60898. Mounts on DIN rail (REG), occupies 4 width units (about 72 mm), and can be installed in any position. Rated 63 A at 40 °C and 45 °C ambient; derates to 60.48 A at 50 °C, 57.96 A at 55 °C, 55.44 A at 60 °C, 52.92 A at 65 °C, and 50.4 A at 70 °C. ## Fit and integration notes Four-pole device, 55 mm installation depth. Finger and back-of-hand safe per the protection class. Silicon-free construction. Surge current resistance rated 5 kA; I²t let-through 70 000 A²·s. Test circuit requires minimum 100 V AC to operate the test button.","metaTitle":"Siemens 5SM1646-8 SENTRON RCCB, 63A 4P Type A 300mA Selectiv","metaDescription":"Siemens 5SM1646-8 SENTRON selective RCCB, 4-pole, 63 A rated at 40 °C, 300 mA Type A, 10 kA SCCR, DIN rail mount. Current lifecycle status. 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":{"Maximum":"45 °C","Minimum":"-25 °C","Rated Value":"50 Hz","Mounting Type":"DIN rail (REG)","Number Of Poles":"4","lifecycle_stage":"current","Mounting Position":"any","Installation Depth":"55 mm","Product Brand Name":"SENTRON","Maximum Permissible":"60 °C","Minimum Permissible":"-40 °C","Operating Frequency":"50 Hz","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","I2t value / permissible":"70 000 A²·s","at 40 °C / rated value":"63 A","at 45 °C / rated value":"63 A","at 50 °C / rated value":"60.48 A","at 55 °C / rated value":"57.96 A","at 60 °C / rated value":"55.44 A","at 65 °C / rated value":"52.92 A","at 70 °C / rated value":"50.4 A","Short-Circuit Current Rating":"10 kA","Product Feature / Silicon-Free":"Yes","acc. to EN 60898 / rated value":"0.8 kA","Position / Of Power Supply Cord":"top or bottom","Let-Through Current / Permissible":"7 500 kA","Protection Against Electrical Shock":"Finger and back-of-hand safe","supply voltage / at AC / rated value":"400 V","Surge Current Resistance / Rated Value":"5 kA","according to IEC 61008-1 / rated value":"0.8 kA","Switching Function / Short-Term Delayed":"No","Tripping Residual Current / Rated Value":"300 mA","operating current / at AC / rated value":"63 A","Supply Voltage / For Testing Equipment / Minimum":"100 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":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=133954&mlfb=5SM1646-8","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SM1646-8/alternatives.json"},"ai":{"faq":[{"question":"How do I get pricing and availability for 5SM1646-8?","answer":"Submit an RFQ through this listing. Availability and current pricing are confirmed at quote time through our sourcing desk."},{"question":"Will 5SM1646-8 drop into a panel specified around 5SY4304-7CV?","answer":"Mechanically yes — both are 4-pole DIN-rail RCCBs, same width units. Functionally no: the 5SM1646-8 is selective (time-delayed), the 5SY4304-7CV is instantaneous. Swapping them changes the coordination plan."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SM1646-8","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/5SM1646-8 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}}