{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB3143-4UX1","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB3143-4UX1","canonicalUrl":"https://aoctrl.com/siemens/3RB3143-4UX1","factsUrl":"https://aoctrl.com/api/mcp/products/3RB3143-4UX1","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RB3143-4UX1 solid-state overload relay, Size S3, 50 A thermal current, adjustable trip classes 5E-30E, straight-through transformers.","salesMarkdown":"The Siemens 3RB3143-4UX1 is a SIRIUS solid-state overload relay, Size S3, with a thermal current of 50 A. Trip class is adjustable across CLASS 5E, 10E, 20E, and 30E, giving you flexibility to match motor start characteristics — fast trip for short starts, slower for high-inertia loads. The relay trips when motor current exceeds the upper current setting value by a factor of 3.5, and resets when current drops below the lower setting. The auxiliary switch is integrated, with switching capacity rated at 2 A at 24 V, 4 A at 120 V, and 3 A at 230 V — enough for a PLC input or contactor coil in most panels. Power dissipation per pole is 0.07 W, so heat buildup in a dense enclosure is minimal. Mounts in any position via stand-alone installation — no DIN rail required, though it can be panel-mounted. Dimensions are 70 mm wide, 106 mm high, 124 mm deep, fitting a standard Size S3 footprint. Vibration resistance is 1-6 Hz at 15 mm amplitude, 6-500 Hz at 20 m/s² for 10 cycles. Shock resistance is 8g for 11 ms on the signaling contact in tripped position, 15g for 11 ms per IEC 60068-2-27 on the main body. That holds up in most industrial machinery environments. Substance prohibitance date is 03/01/2017, confirming RoHS compliance from that date forward.","metaTitle":"Siemens 3RB3143-4UX1 SIRIUS solid-state overload relay, S3,","metaDescription":"Siemens SIRIUS 3RB3143-4UX1 solid-state overload relay, Size S3, 50 A thermal current, adjustable trip classes 5E-30E. Active production. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Overload Relays"],"specifications":{"Note":"for message \"tripped\"","Depth":"124 mm","Solid":"2x (0.25 ... 1.5 mm²)","Width":"70 mm","title":"3RB3143-4UX1","Height":"106 mm","Maximum":"IMotor < upper current setting value x 3.5","Minimum":"IMotor > lower current setting value","at 24 V":"2 A","at 60 V":"0.55 A","Per Pole":"0.07 W","at 110 V":"0.3 A","at 120 V":"4 A","at 125 V":"0.3 A","at 220 V":"0.11 A","at 230 V":"3 A","Trip Class":"CLASS 5E, 10E, 20E and 30E adjustable","Rated Value":"1 000 V","description":"Overload relay 12.5...50 A Electronic For motor protection Size S3, Class 5E...30E Stand-alone installation Main circuit: Straight-through transformer Auxiliary circuit: Spring-type terminal Manual-Automatic-Reset","During Storage":"-40 ... +80 °C","Thermal Current":"50 A","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-40 ... +80 °C","Fastening Method":"stand-alone installation","Shock Resistance":"8g / 11 ms","Mounting Position":"any","Solid Or Stranded":"2x (0,25 ... 1,5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"solid-state overload relay","Vibration Resistance":"1-6 Hz, 15 mm; 6-500 Hz, 20 m/s²; 10 cycles","at 480 V rated value":"50 A","at 600 V rated value":"50 A","Size Of Overload Relay":"S3","For Main Current Circuit":"straight-through transformers","Temperature Compensation":"-25 ... +60 °C","Design Of Screwdriver Shaft":"Diameter 5 to 6 mm","Size Of The Screwdriver Tip":"Pozidriv PZ 2","according to IEC 60068-2-27":"15g / 11 ms; Signaling contact 97 / 98 in position \"Tripped\": 8g / 11 ms","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":"electronic","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"50 A","for AC motors at 500 V at 50 Hz":"11 ... 30 kW","for AC motors at 690 V at 50 Hz":"11 ... 45 kW","for remote-reset function at DC":"24 V","For Auxiliary And Control Circuit":"spring-loaded terminals","Between Main And Auxiliary Circuit":"690 V","Relative Humidity During Operation":"10 ... 95 %","With Type Of Assignment 2 Required":"gG: 200 A","Display Version For Switching Status":"Slide switch","Surge Voltage Resistance Rated Value":"8 kV","With Type Of Coordination 1 Required":"gG: 200 A","for 3-phase motors at 400 V at 50 Hz":"7.5 ... 22 kW","for AWG cables for auxiliary contacts":"2x (24 ... 16)","Between Auxiliary And Auxiliary Circuit":"300 V","due to burst according to IEC 61000-4-4":"2 kV (power ports), 1 kV (signal ports) corresponds to degree of severity 3","reference code according to IEC 81346-2":"F","Finely Stranded With Core End Processing":"2x (0.25 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Finely Stranded Without Core End Processing":"2x (0.25 ... 1.5 mm²)","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"1","number of NO contacts for auxiliary contacts":"1","operational current at AC-3e at 400 V rated value":"50 A","Size Of Contactor Can Be Combined Company-Specific":"S3","electrostatic discharge according to IEC 61000-4-2":"6 kV contact discharge / 8 kV air discharge","Type Of Voltage Supply Via Input/Output Link Master":"No","contact rating of auxiliary contacts according to UL":"B600 / R300","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Response Time Of The Grounding Protection In Settled State":"1 000 ms","Response Value Current Of The Grounding Protection Minimum":"0.75 x IMotor","Arrangement Of Electrical Connectors For Main Current Circuit":"Top and bottom","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gG: 6 A","insulation voltage with degree of pollution 3 at AC rated value":"1 000 V","Product Component Removable Terminal For Auxiliary And Control Circuit":"Yes","power loss [W] for rated value of the current at AC in hot operating state":"0.2 W","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"12.5 ... 50 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/e573d985c47da8f40ebc92f80d3039b6.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=629749&mlfb=3RB3143-4UX1"},"ai":{"faq":[{"question":"What compliance documentation is available?","answer":"RoHS compliance is confirmed with a substance prohibitance date of 03/01/2017. The part is CE-marked as part of the SIRIUS family. Full REACH and IEC documentation can be provided on request with an RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB3143-4UX1","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/3RB3143-4UX1 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}