{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SM1744-0","brand":"Siemens","brandSlug":"siemens","productSlug":"5SM1744-0","canonicalUrl":"https://aoctrl.com/siemens/5SM1744-0","factsUrl":"https://aoctrl.com/api/mcp/products/5SM1744-0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SM1 series, RCCB, 4-pole, type AC, 40 A, 500 mA, 400 V, 10 kA, IP20, DIN rail.","salesMarkdown":"The Siemens SENTRON 5SM1744-0 is a 4-pole residual current operated circuit breaker (RCCB) rated at 40 A and 400 V AC, with a 500 mA tripping residual current. This RCCB carries its full 40 A rating up to 45 °C ambient. Above that, the current must be derated: 38.4 A at 50 °C, 36.8 A at 55 °C, 35.2 A at 60 °C, 33.6 A at 65 °C, and 32 A at 70 °C. If the panel ambient exceeds 45 °C, the derated figure governs the continuous load — not the nameplate 40 A. Snaps onto DIN rail (REG) and occupies 4 width units (roughly 72 mm at 18 mm per unit). Installation depth is 55 mm. Mounting position is unrestricted.","metaTitle":"Siemens 5SM1744-0 SENTRON RCCB, 4-Pole, 40 A, 500 mA, 400 V","metaDescription":"Siemens SENTRON 5SM1744-0 RCCB, 4-pole, type AC, 40 A rated, 500 mA residual, 400 V, 10 kA SCCR. Current lifecycle stage. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Residual Current Breakers (RCCB/RCBO)"],"specifications":{"Solid":"1.5 ... 25 mm²","Stranded":"1.5 ... 25 mm²","at 40 Cel":"40 A","at 45 Cel":"40 A","at 50 Cel":"38.4 A","at 55 Cel":"36.8 A","at 60 Cel":"35.2 A","at 65 Cel":"33.6 A","at 70 Cel":"32 A","Rated Value":"50 Hz","Wertebereich":"-5 ... +45 °C","Mounting type":"DIN rail (REG)","Number of poles":"4","lifecycle_stage":"current","Mounting position":"any","Installation depth":"55 mm","Product brand name":"SENTRON","Ambient temperature":"-40 ... +60 °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":"Instantaneous","Number of width units":"4","Type of fault current":"AC","I2t-value / permissible":"70 000 A²·s","circuit-breaker / Design":"5SM1","Short-circuit current rating":"10 kA","Current / at AC / rated value":"40 A","Product feature / silicon-free":"Yes","Position / of power supply cord":"top or bottom","Protection against electrical shock":"Finger and back-of-hand safe","Supply voltage / at AC / rated value":"400 V","Switching function / short-term delayed":"No","Tripping residual current / rated value":"500 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":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=337383&mlfb=5SM1744-0","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SM1744-0/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source for 5SM1744-0?","answer":"The 5SY4304-7CV is a peer RCCB in the same SENTRON family, but it is a 4-pole type A device (detects pulsed DC as well as AC) with different tripping characteristics. The 5SM1744-0 is type AC only. Verify the fault type requirement before substituting — type AC covers sinusoidal AC faults; type A adds pulsed DC detection for appliances with rectifiers."},{"question":"What conductor sizes does 5SM1744-0 accept?","answer":"Both solid and stranded conductors from 1.5 to 25 mm² are accepted by the screw terminals."},{"question":"Where can I buy 5SM1744-0?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm commitment."},{"question":"Does 5SM1744-0 drop into a panel specified around 5SY4304-7CV without rewiring?","answer":"Both are 4-pole RCCBs on DIN rail with the same width (4 units) and similar terminal ranges. The physical footprint and wiring are compatible, but the 5SM1744-0 is type AC (sinusoidal AC only) while the 5SY4304-7CV is type A (AC plus pulsed DC). If the original specification required type A for circuits with electronics or rectified loads, substitution with type AC may not provide adequate protection."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SM1744-0","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/5SM1744-0 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}}