{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RB1066-2KG0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RB1066-2KG0","canonicalUrl":"https://aoctrl.com/siemens/3RB1066-2KG0","factsUrl":"https://aoctrl.com/api/mcp/products/3RB1066-2KG0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 3RB10 series solid-state overload relay, 3RB1066-2KG0, 200-540 A, class 20 trip curve, MOD.S10/S12 with mounting rails for contactor mounting on 3RT106 or separate mounting.","salesMarkdown":"The Siemens 3RB1066-2KG0 is a solid-state overload relay from the 3RB10 series, rated 200-540 A with a class 20 trip curve. It is designed for motor protection in industrial control panels, providing thermal overload protection for three-phase induction motors. The relay includes mounting rails for direct attachment to 3RT106 contactors or for separate DIN-rail mounting, giving flexibility in panel layout. The 200-540 A current range covers medium-to-large motor loads — think 90 kW to 250 kW at 400 VAC, depending on motor full-load current. The class 20 trip curve means the relay allows 20 seconds of locked-rotor current before tripping, matching NEMA design B and C motor starting characteristics. This is the standard protection class for general-purpose industrial motors driving pumps, fans, and compressors. The solid-state design means no bimetal aging drift, consistent trip accuracy over the relay's service life, and no ambient-temperature compensation issues within the rated range. It also provides a wider adjustment bandwidth than a thermal bimetallic relay of the same frame size. The relay ships with mounting rails for direct attachment to 3RT106 contactors — this is the intended use for a compact motor starter assembly. For panel layouts where the overload relay sits remote from the contactor, the same rails support separate DIN-rail mounting. The MOD.S10/S12 designation indicates the mechanical interface and terminal arrangement; verify the contactor frame size matches before committing the BOM line.","metaTitle":"Siemens 3RB1066-2KG0 Solid-State Overload Relay, 200-540A, C","metaDescription":"Siemens 3RB1066-2KG0 solid-state overload relay, 200-540A, class 20 trip curve. Current lifecycle stage. Mounts on 3RT106 contactors or separately. Sourced to order.","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=351506&mlfb=3RB1066-2KG0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RB1066-2KG0/alternatives.json"},"ai":{"faq":[{"question":"What is the current range and trip class of this overload relay?","answer":"It is rated 200-540 A with a class 20 trip curve, suitable for medium-to-large motor protection."},{"question":"How does this relay mount?","answer":"It includes mounting rails for direct attachment to 3RT106 contactors or for separate DIN-rail mounting."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RB1066-2KG0","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/3RB1066-2KG0 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}}