{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU2126-4DJ0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU2126-4DJ0","canonicalUrl":"https://aoctrl.com/siemens/3RU2126-4DJ0","factsUrl":"https://aoctrl.com/api/mcp/products/3RU2126-4DJ0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, 3RU2126-4DJ0, Size S0, Class 10, 690 V rated, contactor-mount.","salesMarkdown":"It mounts directly onto a contactor, saving panel space and simplifying wiring. The 50/60 Hz operating frequency matches standard mains supplies. The contactor-mount fastening method means no additional DIN-rail clip is required; it snaps onto the contactor's own mounting base. Auxiliary switch is integrated, saving an add-on block for status feedback. The thermal design compensates for ambient temperature from -40°C to +60°C, so the trip curve stays accurate in hot enclosures near motors. It is a direct-mount companion to Siemens SIRIUS contactors of the same S0 frame size. When sourcing, verify the contactor's mounting interface matches the relay's base — the S0 frame is a standard Siemens platform, so fit is consistent across the SIRIUS range. ## Integration notes Main circuit connections accept ring cable lugs; screw terminals with a Pozidriv PZ2 tip are used for the auxiliary circuit. The screwdriver shaft diameter is 5–6 mm, so a standard electrician's screwdriver fits. The relay includes a 'Tripped' message indicator (note on the front), giving immediate visual confirmation of an overload condition without needing to open the panel door.","metaTitle":"Siemens 3RU2126-4DJ0 SIRIUS thermal overload relay, Class 10","metaDescription":"Siemens 3RU2126-4DJ0 SIRIUS thermal overload relay, Size S0, Class 10 trip, 690 V rated, contactor-mount. Active production. Source via RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Note":"for message \"Tripped\"","Depth":"85 mm","Width":"45 mm","Height":"85 mm","at 24 V":"2 A","at 60 V":"0.3 A","Per Pole":"2.7 W","at 110 V":"0.22 A","at 120 V":"3 A","at 125 V":"0.22 A","at 220 V":"0.11 A","at 230 V":"2 A","at 400 V":"1 A","Trip Class":"CLASS 10","Rated Value":"690 V","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-40 ... +70 °C","During Transport":"-55 ... +80 °C","Fastening Method":"Contactor mounting","For Main Contacts":"M4","Mounting Position":"any","Product Brand Name":"SIRIUS","Product Designation":"thermal overload relay","at 400 V rated value":"11 kW","at 480 V rated value":"25 A","at 500 V rated value":"15 kW","at 600 V rated value":"25 A","at 690 V rated value":"22 kW","Size Of Overload Relay":"S0","For Main Current Circuit":"Ring cable lug connection","Temperature Compensation":"-40 ... +60 °C","MTTF with high demand rate":"2 280 y","Design Of Screwdriver Shaft":"Diameter 5 ... 6 mm","Size Of The Screwdriver Tip":"Pozidriv PZ 2","at AC-3e rated value maximum":"690 V","Substance Prohibitance (Date)":"10/01/2009","Design Of The Auxiliary Switch":"integrated","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"25 A","For Auxiliary And Control Circuit":"ring terminal lug connection","Between Main And Auxiliary Circuit":"440 V","Relative Humidity During Operation":"10 ... 95 %","Display Version For Switching Status":"Slide switch","For Main Contacts For Ring Cable Lug":"2.5 ... 2 N·m","Surge Voltage Resistance Rated Value":"6 kV","Of The Auxiliary And Control Contacts":"M3","Between Auxiliary And Auxiliary Circuit":"440 V","reference code according to IEC 81346-2":"F","Number Of Poles For Main Current Circuit":"3","For Auxiliary Contacts For Ring Cable Lug":"0.8 ... 1.2 N·m","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"1","number of NO contacts for auxiliary contacts":"1","shock resistance according to IEC 60068-2-27":"8g / 11 ms","operational current at AC-3e at 400 V rated value":"25 A","Size Of Contactor Can Be Combined Company-Specific":"S0","Outer Diameter Of The Usable Ring Cable Lug Maximum":"7.5 mm","contact rating of auxiliary contacts according to UL":"B600 / R300","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Arrangement Of Electrical Connectors For Main Current Circuit":"Top and bottom","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gG: 6 A, quick: 10 A","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Product Component Removable Terminal For Auxiliary And Control Circuit":"No","power loss [W] for rated value of the current at AC in hot operating state":"8.1 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"20 ... 25 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/7db5fa67265a47a3185af6f2fb84653a.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=464788&mlfb=3RU2126-4DJ0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU2126-4DJ0/alternatives.json"},"ai":{"faq":[{"question":"What is the 'Tripped' note on this relay?","answer":"The relay includes a visual indicator labeled for message 'Tripped', which shows when the thermal overload has been triggered, aiding quick fault diagnosis."},{"question":"What are the key dimensions of the 3RU2126-4DJ0?","answer":"Depth is 85 mm, width is 45 mm, and height is 85 mm. It is a compact Size S0 relay designed for contactor mounting."},{"question":"Will the 3RU2126-4DJ0 fit in a panel designed for a Siemens SIRIUS contactor?","answer":"Yes, it is designed for direct contactor mounting and matches the S0 frame size of Siemens SIRIUS contactors. No additional DIN-rail clip is needed."},{"question":"What compliance documentation is available for this relay?","answer":"The evidence lists a substance prohibition date of 10/01/2009, indicating RoHS compliance. Standard Siemens SIRIUS relays carry CE, UL, and CSA approvals, but specific certificates are not listed in this evidence."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU2126-4DJ0","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/3RU2126-4DJ0 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}}