{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SJ4120-6HG40","brand":"Siemens","brandSlug":"siemens","productSlug":"5SJ4120-6HG40","canonicalUrl":"https://aoctrl.com/siemens/5SJ4120-6HG40","factsUrl":"https://aoctrl.com/api/mcp/products/5SJ4120-6HG40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SJ4120-6HG40, B-curve miniature circuit breaker, 1-pole, 10 kA (EN 60898) / 15 kA (IEC 60947-2), 400 V AC rated, 18 mm width.","salesMarkdown":"Rated 400 V AC and 60 V DC, this MCB handles standard 230/400 V three-phase distribution and low-voltage DC control circuits. The single-pole design switches the line only — no neutral switching, so wire it into the phase leg. The IP20 body (IP40 in the handle area) is fine inside a closed enclosure but not for washdown locations. Vibration resistance is specified at 50 m/s² over 25–150 Hz and 60 m/s² at 35 Hz, so it holds up in machinery with moderate vibration, like conveyors or pumps. ## Integration and installation notes Depth is 70 mm, which is standard for this class — it'll clear a 100 mm enclosure backplate. The sealable design lets you lock the handle position for lockout/tagout compliance without adding an external hasp. Designed for mechanical engineering and industrial applications per the suitability listing. In a typical panel, it protects a lighting circuit, a small control transformer primary, or a PLC power supply feed. The B-curve keeps it from tripping on the short inrush of a 50 VA control transformer, but if you're feeding motor starters, you'd want a C- or D-curve instead.","metaTitle":"Siemens 5SJ4120-6HG40 SENTRON MCB, B-Curve 1P, 10kA/15kA","metaDescription":"Siemens SENTRON 5SJ4120-6HG40 miniature circuit breaker, B-curve, 1-pole, 10 kA per EN 60898, 15 kA per IEC 60947-2. Active production, sourced to order.","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":"5SJ4120-6HG40","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","description":"Miniature circuit breaker 240 V 14kA, 1-pole, B, 20 A, D=70 mm according to UL 489, equal polarity","Halogen-Free":"Yes","Silicon-Free":"Yes","Design Of Pole":"1P","Number Of Poles":"1","lifecycle_stage":"current","Fastening Method":"on standard mounting rail","Mounting Position":"any","at AC rated value":"400 V","at DC rated value":"60 V","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"3","Product Designation":"Miniature circuit breakers","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","Product Function Note":"Terminal tightening torque for Cu, 60/75°C; 3.5Nm/31lb.in","Tunnel Terminals Bottom":"No","Combined Terminal Bottom":"Yes","Suitability For Operation":"Mechanical engineering / industry","at DC rated value maximum":"60 V","Neutral Conductor Switching":"No","Number Of Modular Width Units":"1","Position Of Power Supply Cord":"Any","Tripping Characteristic Class":"B","according to EN 60898 rated value":"10 kA","Ambient Temperature During Operation":"max. 95% humidity","Supply Voltage Frequency Rated Value":"50 Hz","according to IEC 60947-2 rated value":"15 kA","installation environment regarding EMC":"Suitable for environment B (immunity to interference not applicable)","insulation voltage (Ui) at AC rated value":"440 V","Value Range Of The Supply Voltage Frequency":"50/60 Hz","vibration resistance according to IEC 60068-2-6":"±1 mm at 5 to 25 Hz; 50 m/s² at 25 to 150 Hz","Mechanical Service Life (Operating Cycles) Typical":"10 000","Product Extension Installable Supplementary Devices":"Yes","Tightening Torque With Screw-Type Terminals Maximum":"3.5 N·m","power loss [W] for rated value of the current at AC in hot operating state per pole":"2.7 W"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$20.32","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/16e2d62d28ffd64df1a3bddd11d8b181.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=186810&mlfb=5SJ4120-6HG40"},"ai":{"faq":[{"question":"What is the closest functional alternative — will the 5SL6006-7 drop in without rewiring?","answer":"The 5SL6006-7 is a different series (Siemens 5SL) with a similar form factor. Both are single-pole MCBs on 18 mm width, so they share the same DIN-rail footprint and terminal spacing. The deciding factor is the tripping curve and breaking capacity — verify the 5SL unit's B-curve and kA rating match your coordination study before swapping. No rewiring needed if the ratings align; the termination style is the same."},{"question":"What are the key dimensions for panel layout?","answer":"Width is 18 mm (1 modular unit), height is 90 mm, depth is 70 mm. These are standard for a single-pole MCB and fit any 35 mm DIN-rail enclosure with at least 100 mm internal depth."},{"question":"What compliance documentation is available for this MCB?","answer":"The SENTRON series typically ships with CE marking and manufacturer declarations for RoHS and REACH. Specific UL or IEC certification markings should be on the product label; for formal certificates, request them via the RFQ process. The part is rated per EN 60898 (10 kA) and IEC 60947-2 (15 kA), so it carries those design standards."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SJ4120-6HG40","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/5SJ4120-6HG40 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}}