{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU1146-4LB0-ZX95","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU1146-4LB0-ZX95","canonicalUrl":"https://aoctrl.com/siemens/3RU1146-4LB0-ZX95","factsUrl":"https://aoctrl.com/api/mcp/products/3RU1146-4LB0-ZX95","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, Size S3, Trip Class 10, screw-type terminals, 140 mm depth, IP20 front, ATEX certified.","salesMarkdown":"## Thermal Overload Relay for Contactor-Mounted Motor Protection The Siemens 3RU1146-4LB0-ZX95 is a SIRIUS-brand thermal overload relay in Size S3, designed for contactor mounting to protect three-phase motors against overload and phase failure. ## ATEX and Environmental Ratings The front face is IP20, meaning finger-safe once installed in a panel. Shock resistance is 8g for 10 ms, adequate for most industrial machinery but not heavy-crane applications. Mounts directly onto the matching SIRIUS contactor via the contactor-mounting fastening method — no separate base required. The mounting position allows rotation ±135° on a vertical surface and tilting ±45° front-to-back, giving flexibility in tight panels. Main circuit terminals accept screw-type connections: stranded 10–70 mm² (2x 10–50 mm²), or AWG 2x (10–1/0) and 1x (10–2/0). Auxiliary and control circuit terminals accept solid 2x (0.5–1.5 mm²) or 2x (0.75–2.5 mm²), and AWG 2x (20–16) or 2x (18–14). Dimensions: 70 mm wide, 120 mm high, 140 mm deep. ## Auxiliary Contact Ratings and Coordination The built-in auxiliary contacts (typically one N/C + one N/O for the trip/alarm) are rated: 1 A at 24 V, 3 A at 120 V, 2 A at 230 V, 1 A at 400 V, and 0.22 A at 110/125 V, 0.11 A at 220 V. For short-circuit coordination, with Type of Assignment 2 the required upstream fuse is gG 160 A; with Type of Coordination 1 it is gG 250 A. Per-pole power dissipation is 7 W — factor that into panel thermal calculations if the relay is enclosed without ventilation. For a BOM-frozen design, this part is a qualified, stable choice. No official successor has been issued, so this remains the direct drop-in for any panel originally specified with the 3RU1146-4LB0-ZX95.","metaTitle":"Siemens 3RU1146-4LB0-ZX95 SIRIUS Thermal Overload Relay, Siz","metaDescription":"Siemens SIRIUS 3RU1146-4LB0-ZX95 thermal overload relay, Size S3, Trip Class 10, ATEX certified, IP20 front. Current lifecycle. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Depth":"140 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Width":"70 mm","Height":"120 mm","Upwards":"0 mm","at 24 V":"1 A","Forwards":"0 mm","Per Pole":"7 W","Stranded":"2x (10 ... 50 mm²), 10 ... 70 mm²","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":"S3","For Main Current Circuit":"screw-type terminals","Substance Prohibitance (Date)":"07/01/2006","at AWG cables for main contacts":"2x (10 ... 1/0), 1x (10 ... 2/0)","protection class IP on the front":"IP20","For Auxiliary And Control Circuit":"screw-type terminals","Relative Humidity During Operation":"100 %","With Type Of Assignment 2 Required":"gG: 160 A","Surge Voltage Resistance Rated Value":"8 kV","With Type Of Coordination 1 Required":"gG: 250 A","at 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":"S3","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":"1 000 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":"21 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"70 ... 90 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=152894&mlfb=3RU1146-4LB0-ZX95","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU1146-4LB0-ZX95/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source for 3RU1146-4LB0-ZX95?","answer":"The closest functional peer is the Siemens 3RT5046-1AM00 contactor (same SIRIUS Size S3 frame). The 3RU1146-4LB0-ZX95 mounts directly onto that contactor and shares the same footprint and wiring terminals, so a panel built around the 3RT5046-1AM00 can accept this overload relay without rewiring."},{"question":"What compliance documentation does 3RU1146-4LB0-ZX95 carry?","answer":"It carries ATEX approval DMT 98 ATEX G 001 for use in explosive gas atmospheres. The front protection class is IP20. Substance prohibitance date is 07/01/2006 (RoHS compliance)."},{"question":"Where can I buy 3RU1146-4LB0-ZX95 and how is it quoted?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm commercial offer."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU1146-4LB0-ZX95","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/3RU1146-4LB0-ZX95 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}}