{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB1045-2EB0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB1045-2EB0","canonicalUrl":"https://aoctrl.com/siemens/3RB1045-2EB0","factsUrl":"https://aoctrl.com/api/mcp/products/3RB1045-2EB0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RB1045-2EB0 electronic overload relay, 25-100 A, class 20, screw connection, manual reset, size S3, for contactor mounting.","salesMarkdown":"The Siemens 3RB1045-2EB0 is an electronic overload relay in the SIRIUS 3RB10 family, designed to protect three-phase motors against overload and phase imbalance. It mounts directly onto a matching contactor (size S3 footprint) and uses screw terminals for power and control wiring. The relay is set for Class 20 trip curve — meaning it allows up to 20 seconds of locked-rotor current before tripping, which suits standard motor starting profiles on pumps, fans, and conveyors. Reset is manual only, so the relay stays tripped until an operator physically presses the reset button, preventing automatic restart after a fault. The 25 to 100 A adjustment range covers a wide band of motor full-load currents — from a 7.5 kW motor on the low end up to about 45 kW at 400 V (assuming a typical 2.2 A/kW rule of thumb). The screw connection is a straightforward field termination — no special tooling beyond a screwdriver, and it accepts stranded or solid copper up to the terminal rating. Size S3 means the relay shares the mounting profile with S3 contactors (e.g., Siemens 3RT10 series), so it clips directly onto the contactor without extra DIN-rail space.","metaTitle":"Siemens 3RB1045-2EB0 Electronic Overload Relay, 25-100A, Cla","metaDescription":"Siemens 3RB1045-2EB0 electronic overload relay, 25-100A, class 20, screw connection, manual reset, size S3. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Overload Relays"],"specifications":{"lifecycle_stage":"current"}},"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=132887&mlfb=3RB1045-2EB0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RB1045-2EB0/alternatives.json"},"ai":{"faq":[{"question":"What is the adjustment range and trip class of this overload relay?","answer":"The 3RB1045-2EB0 adjusts from 25 to 100 A and is a Class 20 device, meaning it allows up to 20 seconds of locked-rotor current before tripping."},{"question":"Does this relay have automatic or manual reset?","answer":"It has manual reset only — the relay stays tripped until an operator physically presses the reset button, preventing automatic restart after a fault."},{"question":"What contactor size does this relay mount to?","answer":"It is size S3 and mounts directly onto Siemens S3 contactors (e.g., 3RT10 series) without requiring extra DIN-rail space."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB1045-2EB0","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/3RB1045-2EB0 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}}