{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU2126-4DC0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU2126-4DC0","canonicalUrl":"https://aoctrl.com/siemens/3RU2126-4DC0","factsUrl":"https://aoctrl.com/api/mcp/products/3RU2126-4DC0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RU2126-4DC0 thermal overload relay, CLASS 10, S0 size, 690 V rated, spring-loaded terminals, contactor mounting.","salesMarkdown":"## CLASS 10 trip curve and motor protection The 3RU2126-4DC0: This is the standard trip class for general-purpose motor starting — it allows the motor to accelerate through inrush without nuisance tripping while still protecting against locked-rotor conditions. The 480 V and 600 V ratings both list 25 A, which matches the S0 frame size current ceiling. ## S0 frame and contactor mounting Size S0 overload relay, 45 mm wide, 84 mm deep, 102 mm tall. Mounts directly onto the matching SIRIUS contactor — no DIN rail bracket needed. The fastening method is contactor mounting, and the relay can be installed in any position. ## Active production and sourcing Temperature compensation is active from -40 to +60 °C, keeping the trip curve accurate across the typical panel environment.","metaTitle":"Siemens 3RU2126-4DC0 SIRIUS Thermal Overload Relay, CLASS 10","metaDescription":"Siemens 3RU2126-4DC0 SIRIUS thermal overload relay, CLASS 10 trip, S0 size, 690 V rated. Spring-loaded terminals, contactor mounting.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Overload Relays"],"specifications":{"Note":"for message \"Tripped\"","Depth":"84 mm","Width":"45 mm","title":"3RU2126-4DC0","Height":"102 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","at 690 V":"0.75 A","Trip Class":"CLASS 10","Rated Value":"690 V","description":"Overload relay 20...25 A Thermal For motor protection Size S0, Class 10 Contactor mounting Main circuit: Spring-type terminal Auxiliary circuit: spring-type terminal Manual-Automatic-Reset","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-40 ... +70 °C","During Transport":"-55 ... +80 °C","Fastening Method":"Contactor mounting","Mounting Position":"any","Solid Or Stranded":"2x (0.5 ... 2.5 mm²)","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":"spring-loaded terminals","Temperature Compensation":"-40 ... +60 °C","MTTF with high demand rate":"2 280 a","Design Of Screwdriver Shaft":"Diameter 3 mm","Size Of The Screwdriver Tip":"3,0 x 0,5 mm","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","at AWG cables for main contacts":"1x (18 ... 8)","For Auxiliary And Control Circuit":"spring-loaded terminals","Between Main And Auxiliary Circuit":"440 V","Relative Humidity During Operation":"10 ... 95 %","Display Version For Switching Status":"Slide switch","Surge Voltage Resistance Rated Value":"6 kV","at AWG cables for auxiliary contacts":"2x (20 ... 14)","Between Auxiliary And Auxiliary Circuit":"440 V","reference code according to IEC 81346-2":"F","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Number Of Poles For Main Current Circuit":"3","Finely Stranded Without Core End Processing":"2x (0.5 ... 1.5 mm²)","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","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,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/46261b6e15e8f01eb1695a91af24c40b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=456228&mlfb=3RU2126-4DC0"},"ai":{"faq":[{"question":"What does the 'Note for message Tripped' mean on the 3RU2126-4DC0?","answer":"The note indicates the relay has a built-in auxiliary contact that changes state when the overload trips, providing a signal that can be wired to a PLC input or indicator lamp for remote fault indication."},{"question":"What is the depth of the 3RU2126-4DC0?","answer":"The depth is 84 mm, with a width of 45 mm and height of 102 mm. It mounts directly onto the SIRIUS contactor."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU2126-4DC0","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/3RU2126-4DC0 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}