{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU2126-1CB0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU2126-1CB0","canonicalUrl":"https://aoctrl.com/siemens/3RU2126-1CB0","factsUrl":"https://aoctrl.com/api/mcp/products/3RU2126-1CB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS, thermal overload relay, 3RU2126-1CB0, Class 10, S0 size, 690 V rated, screw-type terminals, contactor mounting.","salesMarkdown":"The CLASS 10 trip class governs how fast the bimetal strip deflects under overload. Power dissipation per pole is 1.9 W. That's typical for an S0 frame and adds up to about 5.7 W total for three-phase. Not negligible if you're packing relays tightly, but within the free-air rating of the contactor assembly. The relay is temperature-compensated from -40 to +60 °C, so it won't drift with ambient changes in a warm panel. ## Mounting and wiring detail Fastening method is 'Contactor mounting' — it clips onto the output side of a Siemens SIRIUS contactor of the S0 frame. No additional DIN rail is needed; it snaps directly onto the contactor's three terminals and is mechanically interlocked. Main circuit terminals are screw-type, accepting two conductors per pole: 2x 0.5…1.5 mm² or 2x 0.75…2.5 mm². The screwdriver shaft must be 5-6 mm diameter with a Pozidriv PZ2 tip. The brand is Siemens SIRIUS, and the product designation is 'thermal overload relay'. Compliance-wise, there's a substance prohibitance date of 10/01/2009 which aligns with RoHS — that means the relay was designed to be lead-free and RoHS-compliant from that date onward. If you need a formal RoHS or REACH declaration, we can provide that with the RFQ.","metaTitle":"Siemens 3RU2126-1CB0 SIRIUS Thermal Overload Relay, Class 10","metaDescription":"Active SIRIUS thermal overload relay, S0 size, Class 10 trip, 690 V rated, screw terminals, contactor mounting. Sourced to order via RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Overload Relays"],"specifications":{"Note":"for message \"Tripped\"","Depth":"85 mm","Width":"45 mm","title":"3RU2126-1CB0","Height":"85 mm","at 24 V":"2 A","at 60 V":"0.3 A","Per Pole":"1.9 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 1.8...2.5 A Thermal For motor protection Size S0, Class 10 Contactor mounting Main circuit: Screw Auxiliary circuit: Screw 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","For Main Contacts":"M4","Mounting Position":"any","Solid Or Stranded":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"thermal overload relay","at 400 V rated value":"0.75 kW","at 480 V rated value":"2.5 A","at 500 V rated value":"1.1 kW","at 600 V rated value":"2.5 A","at 690 V rated value":"1.5 kW","Size Of Overload Relay":"S0","For Main Current Circuit":"screw-type terminals","Temperature Compensation":"-40 ... +60 °C","MTTF with high demand rate":"2 280 a","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":"2.5 A","at AWG cables for main contacts":"2x (20 ... 16), 2x (20 ... 18), 2x 12","For Auxiliary And Control Circuit":"screw-type 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 ... 16), 2x (18 ... 14)","Of The Auxiliary And Control Contacts":"M3","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","For Main Contacts With Screw-Type Terminals":"2 ... 2.5 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","For Auxiliary Contacts With Screw-Type Terminals":"0.8 ... 1.2 N·m","operational current at AC-3e at 400 V rated value":"2.5 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":"5.7 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"1.8 ... 2.5 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$122.52","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/4df2101db9c74794a6a36a4bcd15e7f2.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=494015&mlfb=3RU2126-1CB0"},"ai":{"faq":[{"question":"What does the 'Tripped' note mean on this relay?","answer":"That note indicates the auxiliary switch integrated into the relay provides a contact that closes when the overload relay trips, signaling a fault condition."},{"question":"What is the depth of the 3RU2126-1CB0?","answer":"The depth is 85 mm, width 45 mm, height 85 mm."},{"question":"Will this relay fit under a Siemens contactor of frame S0?","answer":"Yes, it is designed for direct contactor mounting on the S0 size."},{"question":"What compliance documentation does Siemens provide for this part?","answer":"The relay has a substance prohibitance date of 10/01/2009 indicating RoHS compliance. Further declarations (REACH, UL) can be provided upon request with an RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU2126-1CB0","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/3RU2126-1CB0 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}}