{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SJ4105-8HG42","brand":"Siemens","brandSlug":"siemens","productSlug":"5SJ4105-8HG42","canonicalUrl":"https://aoctrl.com/siemens/5SJ4105-8HG42","factsUrl":"https://aoctrl.com/api/mcp/products/5SJ4105-8HG42","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SJ4 series miniature circuit breaker, 1-pole, D tripping characteristic, 0.5 A rated current, 10 kA breaking capacity per EN 60898, 18 mm width.","salesMarkdown":"The Siemens SENTRON 5SJ4105-8HG42 is a 1-pole miniature circuit breaker (MCB) with a D tripping characteristic, rated 0.5 A at AC and 10 kA breaking capacity per EN 60898. At 30 °C and 40 °C the breaker holds a full 0.5 A. Above that, it derates linearly: 0.48 A at 45 °C, 0.46 A at 50 °C, 0.44 A at 55 °C, and 0.42 A at 60 °C. If your panel ambient runs 50 °C — common in a sealed cabinet with drives — you have 0.46 A of headroom, not 0.5 A. That derating curve is the real selection number, not the label. ## DC rating and application fit The DC side is rated 60 V maximum. That covers 24 VDC control circuits and 48 VDC signal loops, but not a 110 VDC battery bank. For DC applications, the D curve's magnetic trip threshold (10–20× In) means it will hold through a capacitor bank charge cycle, but verify the DC voltage does not exceed 60 V.","metaTitle":"Siemens SENTRON 5SJ4105-8HG42 MCB, 1-pole D-curve, 0.5 A, 10","metaDescription":"Siemens SENTRON 5SJ4105-8HG42 miniature circuit breaker, 1-pole, D tripping characteristic, 0.5 A rated, 10 kA breaking capacity per EN 60898, 18 mm wide, current production.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["1-Pole MCB (DIN Rail)"],"specifications":{"Depth":"70 mm","Width":"18 mm","title":"5SJ4105-8HG42","Height":"121 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","description":"Circuit breaker 10kA, 1-pole, D, 0.5 A according to UL 489-277V","Halogen-Free":"Yes","Silicon-Free":"Yes","Number Of Poles":"1","lifecycle_stage":"current","Fastening Method":"on standard mounting rail","Mounting Position":"any","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"3","Product Designation":"Miniature circuit breakers","acc. to IEC 81346-2":"F","at AC / rated value":"0.5 A","protection class IP":"IP20, with connected conductors, IP 40 in the handle range","Overvoltage Category":"3","Tunnel Terminals Top":"No","Vibration Resistance":"50 m/s² at 25 to 150Hz and 60m/s² at 35Hz (4sec)","Combined Terminal Top":"Yes","Design Of The Product":"Miniature circuit-breaker 5SJ4","acc. to DIN EN 61346-2":"F","Product Function / Note":"Terminal tightening torque for Cu, 60/75°C; 3.5Nm/31lb.in","Tunnel Terminals Bottom":"No","at 30 °C / rated value":"0.5 A","at 40 °C / rated value":"0.5 A","at 45 °C / rated value":"0.48 A","at 50 °C / rated value":"0.46 A","at 55 °C / rated value":"0.44 A","at 60 °C / rated value":"0.42 A","Combined Terminal Bottom":"Yes","Suitability For Operation":"Mechanical engineering / industry","Number Of Modular Width Units":"1","Tripping Characteristic Class":"D","at DC / rated value / maximum":"60 V","acc. to EN 60898 / rated value":"10 kA","Position / Of Power Supply Cord":"Any","acc. to IEC 60947-2 / rated value":"15 kA","Product Feature / Touch Protection":"Yes","supply voltage / at AC / rated value":"400 V","installation environment regarding EMC":"Suitable for environment B (immunity to interference not applicable)","insulation voltage (Ui) / at AC / rated value":"440 V","Product Component / Neutral Conductor Switching":"No","Mechanical Service Life (Switching Cycles) / Typical":"10 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$38.10 – $98.98","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/828c5adc8c6a21a256b12e8fdce0be3f.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=279330&mlfb=5SJ4105-8HG42"},"ai":{"faq":[{"question":"What are the key ratings for this MCB?","answer":"It is a 1-pole D-curve breaker rated 0.5 A AC, with a 10 kA breaking capacity per EN 60898. DC rating is 60 V max. Thermal derating starts above 40 °C."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SJ4105-8HG42","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/5SJ4105-8HG42 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}