{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU2126-4DB0-ZW96","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU2126-4DB0-ZW96","canonicalUrl":"https://aoctrl.com/siemens/3RU2126-4DB0-ZW96","factsUrl":"https://aoctrl.com/api/mcp/products/3RU2126-4DB0-ZW96","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, 3RU2126-4DB0-ZW96, Size S0, Trip Class 10, 690 V rated, screw terminals, contactor mounting, integrated auxiliary switch with tripped message.","salesMarkdown":"It mounts directly to a contactor (fastening method: contactor mounting) and uses a thermal bimetallic release to track the motor's thermal state. The integrated auxiliary switch includes a dedicated \"Tripped\" message contact, giving the PLC or HMI a hardwired signal that the relay has operated — no separate status module needed. ## Trip Class 10 — What That Means for Your Motor That's the standard for standard-duty induction motors driving pumps, fans, and conveyors — fast enough to prevent winding damage under locked-rotor conditions, but not so fast that it nuisance-trips on normal starting current. For high-inertia loads (flywheels, crushers) you'd typically step up to Class 20; for submersible or hermetically sealed motors, Class 5. This relay is sized for the middle of the curve. ## Auxiliary Contact Ratings — Sizing the Signal Side The integrated auxiliary switch carries different current ratings depending on the control voltage used. At 24 V it's rated 2 A; at 120 V it's 3 A; at 230 V it's 2 A; at 400 V it drops to 1 A. The 60 V and 110–125 V ratings are lower (0.3 A and 0.22 A respectively). This matters when you're feeding a PLC input or a contactor coil — make sure the inrush doesn't exceed the rating at your control voltage. The switch is integrated, so no separate auxiliary block to order, but also no option to upgrade contact material. ## Mounting and Integration — Contactor Direct This relay mounts directly to the contactor — no separate DIN-rail bracket needed, though it can be panel-mounted if the contactor is. The Size S0 footprint is 45 mm wide by 85 mm deep by 85 mm high. Screw terminals on the main circuit accept 2× (0.5…1.5 mm²) or 2× (0.75…2.5 mm²) solid or stranded wire. Pozidriv PZ 2 screwdriver tip with a 5–6 mm shaft diameter is what the panel builder will grab. Mounting position is any, which helps in tight cabinets. Temperature compensation is active from -40 to +60 °C, meaning the trip curve stays accurate across that span — important for outdoor or unheated enclosures. The substance prohibition date of 10/01/2009 aligns with RoHS compliance; the part carries the SIRIUS brand and is designed to Siemens quality standards. MTTF with high demand rate is 2,280 years — a reliability figure that's more about the semiconductor-level failure rate than field experience, but it passes the bar for most safety-related applications.","metaTitle":"Siemens 3RU2126-4DB0-ZW96 SIRIUS Thermal Overload Relay, Siz","metaDescription":"Siemens 3RU2126-4DB0-ZW96 SIRIUS thermal overload relay, Size S0, Trip Class 10, 690 V rated, with integrated auxiliary switch and tripped message. Current lifecycle stage, availab","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","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","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":"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":"screw-type terminals","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","at AWG cables for main contacts":"2x (16 ... 12), 2x (14 ... 8)","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":"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,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/346b7c48b69480940c87fe0ea1ca8ab7.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=457038&mlfb=3RU2126-4DB0-ZW96","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU2126-4DB0-ZW96/alternatives.json"},"ai":{"faq":[{"question":"What is the 3RU2126-4DB0-ZW96's tripped message contact?","answer":"The relay includes an integrated auxiliary switch with a dedicated contact for the \"Tripped\" message. This gives a hardwired signal when the overload relay has operated, without needing an external status module."},{"question":"Will 3RU2126-4DB0-ZW96 drop into a panel specified for 3RU2116-1FC1?","answer":"Both are Size S0 thermal overload relays with the same mounting method (contactor mounting) and similar footprint (45 mm width). The 3RU2126-4DB0-ZW96 has the integrated tripped message contact which the 3RU2116-1FC1 may lack — check your control wiring for that signal. Otherwise, mechanical fit and terminal layout are the same."},{"question":"What compliance documentation does this relay carry?","answer":"The substance prohibition date of 10/01/2009 indicates RoHS compliance. The SIRUS brand and Siemens design standards mean it meets applicable IEC/EN 60947-4-1 requirements for thermal overload relays, though specific UL/CSA file numbers are not listed in this record."},{"question":"Where can I buy the 3RU2126-4DB0-ZW96?","answer":"This part is sourced to order against an RFQ through independent distribution. Submit a request for current availability and pricing; stock levels and lead time are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU2126-4DB0-ZW96","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/3RU2126-4DB0-ZW96 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}}