{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU1126-1KB0-ZW97","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU1126-1KB0-ZW97","canonicalUrl":"https://aoctrl.com/siemens/3RU1126-1KB0-ZW97","factsUrl":"https://aoctrl.com/api/mcp/products/3RU1126-1KB0-ZW97","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, 3RU1126-1KB0-ZW97, CLASS 10 trip, S0 frame, screw-type terminals, ATEX certified.","salesMarkdown":"Mounting is via direct contactor attachment (fastening method: contactor mounting), so it snaps onto the matching SIRIUS contactor without additional DIN-rail space. The relay carries DMT 98 ATEX G 001 certification, meaning it is approved for use in potentially explosive gas atmospheres — a requirement for Zone 1 or Zone 2 motor circuits in chemical, oil-and-gas, or grain-handling plants. The front panel is IP20 rated, finger-safe per IEC 60529, so it can sit on an open panel door without additional guarding. If your motor has a longer acceleration time (high-inertia loads like centrifuges or large flywheels), you would typically step up to CLASS 20 or CLASS 30 — but that is a different relay, not this one. The S0 frame size is the mid-range in the SIRIUS family, physically fitting contactors in the same S0 envelope. Clearance requirements: 0 mm upward, forward, backward, and downward; 6 mm at the side. That zero-clearance top and bottom means you can stack contactors directly without leaving an air gap, but the 6 mm side gap must be maintained for heat dissipation. The solid/stranded wire range is 2× (0.5…1.5 mm²) and 2× (0.75…2.5 mm²) for the auxiliary contacts, with AWG equivalents of 2× (20…16) and 2× (18…14). For the main circuit, the same ranges apply. This covers most control wiring up to 2.5 mm² — standard for motor control centers. Auxiliary contact ratings: at 24 V it switches 1 A; at 120 V, 3 A; at 230 V, 2 A; at 400 V, 1 A. ## Environmental and electrical robustness Relative humidity during operation can hit 100% — no derating needed for condensing environments, which is common in washdown or outdoor installations. Shock resistance is 8g for 10 ms, adequate for most industrial vibration profiles (pumps, conveyors, compressors). Surge voltage withstand is rated at 6 kV, which matches the impulse voltage category for 400 V industrial circuits (overvoltage category III per IEC 60664). This means the relay can handle switching transients from contactor coils and motor starts without internal flashover. Heat dissipation per pole is 2.2 W. For a three-pole relay at full load, that is 6.6 W total — modest, but in a densely packed panel with multiple relays side by side, the cumulative heat can raise ambient temperature above the 70 °C limit. The 6 mm side clearance is the critical spacing to keep that heat manageable.","metaTitle":"Siemens 3RU1126-1KB0-ZW97 SIRIUS Thermal Overload Relay, CLA","metaDescription":"Siemens 3RU1126-1KB0-ZW97 SIRIUS thermal overload relay, CLASS 10 trip, S0 frame, screw terminals, ATEX certified. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Depth":"96 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Width":"45 mm","Height":"97 mm","Upwards":"0 mm","at 24 V":"1 A","Forwards":"0 mm","Per Pole":"2.2 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","Backwards":"0 mm","Downwards":"0 mm","Trip Class":"CLASS 10","At The Side":"6 mm","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-20 ... +70 °C","During Transport":"-55 ... +80 °C","Fastening Method":"Contactor mounting","Shock Resistance":"8g / 10 ms","Mounting Position":"with vertical mounting surface +/-135° rotatable, with vertical mounting surface +/- 45° tiltable to the front and back","Product Brand Name":"SIRIUS","Type Of Protection":"DMT 98 ATEX G 001","Product Designation":"thermal overload relay","Size Of Overload Relay":"S0","For Main Current Circuit":"screw-type terminals","Substance Prohibitance (Date)":"07/01/2006","protection class IP on the front":"IP20","For Auxiliary And Control Circuit":"screw-type terminals","Relative Humidity During Operation":"100 %","Surge Voltage Resistance Rated Value":"6 kV","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14)","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","Touch Protection Against Electrical Shock":"finger-safe","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"1","number of NO contacts for auxiliary contacts":"1","Size Of Contactor Can Be Combined Company-Specific":"S0","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/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":"6.6 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"9 ... 12.5 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=238542&mlfb=3RU1126-1KB0-ZW97","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU1126-1KB0-ZW97/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RU1126-1KB0-ZW97?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"What compliance documentation does this relay carry?","answer":"It carries DMT 98 ATEX G 001 certification for explosive gas atmospheres. The substance prohibitance date per RoHS/REACH is listed as 07/01/2006. The reference code per IEC 81346-2 is F (protective device)."},{"question":"What is the closest functional alternative to 3RU1126-1KB0-ZW97?","answer":"The 3RU2116-1FC1 is a peer in the SIRIUS family but belongs to a different size/frame. The 3RU1126-1KB0-ZW97 is an S0 frame with CLASS 10 trip; the 3RU2116-1FC1 is a different frame size. They are not direct drop-in replacements without verifying the mounting interface and current range."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU1126-1KB0-ZW97","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/3RU1126-1KB0-ZW97 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}}