{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RU2146-4KB1","brand":"Siemens","brandSlug":"siemens","productSlug":"3RU2146-4KB1","canonicalUrl":"https://aoctrl.com/siemens/3RU2146-4KB1","factsUrl":"https://aoctrl.com/api/mcp/products/3RU2146-4KB1","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS thermal overload relay, Size S3, 3RU2146-4KB1, Trip Class 10, 37 kW at 400 V rated value, 65 A at 480 V rated value, screw-type terminals.","salesMarkdown":"The 37 kW at 400 V rated value and 65 A at 480 V rated value define the maximum motor power and full-load current the relay can protect at those voltages; match these to your motor nameplate, not the contactor rating. The relay mounts standalone (fastening method: stand-alone installation) in any position, so panel integration is flexible — no forced orientation. ## Key specs that decide the wiring and panel fit Terminals are screw-type for the main current circuit, accepting solid conductors 2x (2.5... 16 mm²) and stranded 2x (6... 16 mm²), 2x (10... 50 mm²), or 1x (10... 70 mm²). The screwdriver drive is a 4 mm hexagon socket — no Phillips or slotted head, so have the correct bit on hand. Auxiliary contacts are integrated, rated at 2 A at 24 V, 3 A at 120 V, 2 A at 230 V, and 1 A at 400 V. Temperature compensation is active from -40 to +60 °C, with operating range -40 to +70 °C. During operation, the relay dissipates 6.3 W per pole. ## What the Note for message Tripped means The evidence lists a Note for message Tripped. This is the diagnostic signal the relay sends when it has operated — a tripped-state indication that can be wired into a PLC or control system to trigger an alarm or shutdown sequence. It is not a fault code; it is a binary status output that confirms the relay has opened the motor circuit due to overload or phase loss.","metaTitle":"Siemens 3RU2146-4KB1 SIRIUS Thermal Overload Relay, Size S3,","metaDescription":"Siemens 3RU2146-4KB1 SIRIUS thermal overload relay, Size S3, Trip Class 10. Rated 37 kW at 400 V, 65 A at 480 V. Current lifecycle. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Overload Relays"],"specifications":{"Note":"for message \"Tripped\"","Depth":"140 mm","Solid":"2x (2.5 ... 16 mm²)","Width":"70 mm","Height":"120 mm","at 24 V":"2 A","at 60 V":"0.3 A","Per Pole":"6.3 W","Stranded":"2x (6 ... 16 mm²), 2x (10 ... 50 mm²), 1x (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","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":"stand-alone installation","For Main Contacts":"M8","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":"37 kW","at 480 V rated value":"65 A","at 500 V rated value":"45 kW","at 600 V rated value":"62 A","at 690 V rated value":"55 kW","Size Of Overload Relay":"S3","For Main Current Circuit":"screw-type terminals","Temperature Compensation":"-40 ... +60 °C","Design Of Screwdriver Shaft":"Hexagonal socket","Size Of The Screwdriver Tip":"4 mm hexagon socket","at AC-3e rated value maximum":"1 000 V","Substance Prohibitance (Date)":"03/01/2017","Design Of The Auxiliary Switch":"integrated","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"75 A","at AWG cables for main contacts":"2x (10 ... 1/0), 1x (10 ... 2/0)","For Auxiliary And Control Circuit":"screw-type terminals","Between Main And Auxiliary Circuit":"440 V","Relative Humidity During Operation":"10 ... 95 %","With Type Of Assignment 2 Required":"gG: 160 A","Display Version For Switching Status":"Slide switch","For Main Contacts For Ring Cable Lug":"4.5 ... 6 N·m","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)","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":"4.5 ... 6 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":"75 A","Size Of Contactor Can Be Combined Company-Specific":"S3","Outer Diameter Of The Usable Ring Cable Lug Maximum":"19 mm","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":"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":"18.9 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"57 ... 75 A","Design Of The Miniature Circuit Breaker For Short-Circuit Protection Of The Auxiliary Switch Required":"6A (SCC less than equal to 0.5 kA; U less than equal to 260V)"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/399b2cdd581d0f1bbcf94daf0a170f1a.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=630108&mlfb=3RU2146-4KB1","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RU2146-4KB1/alternatives.json"},"ai":{"faq":[{"question":"Who supplies 3RU2146-4KB1 and how is it quoted?","answer":"It is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at the time of quote."},{"question":"What is the closest functional second-source to 3RU2146-4KB1?","answer":"The 3RU2116-1FC1 is a SIRIUS thermal overload relay but in a smaller Size S2 form factor. It will not drop into a panel wired for the S3 3RU2146-4KB1 without rewiring and a different mounting footprint. The 3RU2146-4KB1 is the larger S3 frame for higher current ratings."},{"question":"What is the Note for message Tripped on this relay?","answer":"It is a diagnostic signal indicating the relay has tripped due to overload or phase loss — a binary status output for a PLC or alarm circuit."},{"question":"What is the depth of 3RU2146-4KB1?","answer":"The depth is 140 mm, with a width of 70 mm and height of 120 mm, fitting the standard S3 overload relay footprint."},{"question":"Will 3RU2146-4KB1 drop into a panel specified around 3RU2116-1FC1?","answer":"No. The 3RU2146-4KB1 is Size S3 (70 mm wide, 140 mm deep) while the 3RU2116-1FC1 is Size S2. The mounting hole pattern and DIN-rail footprint differ, and the terminal capacity is larger on the S3. Rewiring and re-drilling the panel would be required."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RU2146-4KB1","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/3RU2146-4KB1 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}}