{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU7146-4LB0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU7146-4LB0","canonicalUrl":"https://aoctrl.com/siemens/3RU7146-4LB0","factsUrl":"https://aoctrl.com/api/mcp/products/3RU7146-4LB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS S3 thermal overload relay, 3RU7146-4LB0, rated 90 A, Trip Class 10, screw-type terminals, IP20 front / IP00 terminal, contactor-mount.","salesMarkdown":"The Siemens 3RU7146-4LB0 is a SIRIUS S3 thermal overload relay, rated for 90 A operational current in the main circuit with a Trip Class 10 characteristic. It mounts directly onto a matching S3 contactor — no separate base or DIN-rail adapter needed, which keeps the panel footprint tight and the wiring loom short. The 90 A rated current sets the motor FLA ceiling this relay can protect. If your motor has a longer acceleration ramp (high-inertia loads like centrifuges), you'd want a Class 20 or 30 relay instead; this one would nuisance-trip. The IP20 rating on the front means the operator interface is finger-safe; the IP00 terminal area expects the panel builder to provide the enclosure protection. Screw-type terminals on both main and auxiliary circuits accept 2x (0.5…1.5 mm²) solid or stranded, or 2x (0.75…2.5 mm²) — torque the main contacts to 4–6 N·m, aux contacts to 0.8–1.2 N·m. Fastens directly to a SIRIUS S3 contactor — no DIN rail required, though the relay itself can be mounted on a vertical surface with ±135° rotation or ±45° tilt front-to-back. Side spacing to grounded parts: 6 mm minimum. Operating temperature range –20 to +55 °C; storage/transport –25 to +70 °C. Installation altitude limited to 2000 m. Dimensions: 120 mm high × 70 mm wide × 140 mm deep. The depth is the dimension that extends behind the panel face when contactor-mounted — check your enclosure depth if retrofitting into a shallow cabinet. Total typical power loss at rated current: 21 W.","metaTitle":"Siemens 3RU7146-4LB0 SIRIUS Thermal Overload Relay, 90 A, Cl","metaDescription":"Siemens 3RU7146-4LB0 SIRIUS S3 thermal overload relay, 90 A rated current, Trip Class 10, contactor-mount, IP20 front. Active production. Sourced to order against an RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"Depth":"140 mm","Width":"70 mm","Height":"120 mm","at 24 V":"3 A","Per Pole":"7 W","at 230 V":"2 A","Trip Class":"CLASS 10","On The Front":"IP20","Of The Terminal":"IP00","lifecycle_stage":"current","During Operation":"-20 ... +55 °C","During Transport":"-25 ... +70 °C","Fastening Method":"Contactor mounting","Mounting Position":"with vertical mounting surface +/-135° rotatable, with vertical mounting surface +/- 45° tiltable to the front and back","Solid Or Stranded":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Thermal overload relay","Size Of Overload Relay":"S3","For Main Current Circuit":"screw-type terminals","power loss [W] total typical":"21 W","Operating Voltage Rated Value":"1 000 V","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"90 A","For Auxiliary And Control Circuit":"screw-type terminals","Relative Humidity During Operation":"0 ... 90 %","Surge Voltage Resistance Rated Value":"8 kV","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","Type Of Voltage For Main Current Circuit":"AC/DC","For Main Contacts With Screw-Type Terminals":"4 ... 6 N·m","shock resistance according to IEC 60068-2-27":"8g / 10 ms","Required Spacing For Grounded Parts At The Side":"6 mm","For Auxiliary Contacts With Screw-Type Terminals":"0.8 ... 1.2 N·m","Size Of Contactor Can Be Combined Company-Specific":"S3","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","operational current of auxiliary contacts at DC-13 at 24 V":"1 A","Arrangement Of Electrical Connectors For Main Current Circuit":"Top and bottom","insulation voltage with degree of pollution 3 at AC rated value":"1 000 V","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","Design Of The Fuse Link For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 6 A, quick: 10 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/e6f2be02e61b2eeb95a50c60fc5163d4.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1542629&mlfb=3RU7146-4LB0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU7146-4LB0/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source for 3RU7146-4LB0?","answer":"The SIRIUS S3 contactor family (e.g., 3RT1044-1FB46) shares the same mounting footprint and terminal arrangement. The 3RU7146-4LB0 is designed to drop onto that contactor without rewiring — same S3 size, same screw-type terminal layout. No need to gut the existing panel layout if you're swapping the overload relay only."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU7146-4LB0","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/3RU7146-4LB0 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}}