{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA2125-1FH24-0FB4","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA2125-1FH24-0FB4","canonicalUrl":"https://aoctrl.com/siemens/3RA2125-1FH24-0FB4","factsUrl":"https://aoctrl.com/api/mcp/products/3RA2125-1FH24-0FB4","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA2125-1FH24-0FB4 direct-on-line motor starter, 1.5 kW at 400 V, Class 10, size S0, for 60 mm busbar systems, spring-loaded terminals.","salesMarkdown":"## SIRIUS direct-on-line starter for 60 mm busbar systems The 3RA2125-1FH24-0FB4 is a Siemens SIRIUS direct-on-line starter — a pre-assembled combination of a contactor, overload relay, and circuit breaker in one S0 footprint that snaps onto a 60 mm busbar system. ## Supplied components and wiring terminals The starter ships with the contactor 3RT2024-2FB40, the link module 3RA2921-2AA00, the circuit breaker 3RV2021-1FA25, and the busbar adapter 8US1251-5NT11. Both main and auxiliary/control circuits use spring-loaded terminals — no screw torque to verify, just strip and push. Rated operating frequency is 50 to 60 Hz; maximum voltage in AC-3 duty is 690 V. The unit is designed for vertical mounting only, with clearances: 50 mm upwards, 20 mm forwards, 10 mm downwards, and 20 mm at the side. Backwards clearance is zero — the busbar adapter sits flush.","metaTitle":"Siemens 3RA2125-1FH24-0FB4 SIRIUS Motor Starter","metaDescription":"Siemens 3RA2125-1FH24-0FB4 SIRIUS direct-on-line starter, 1.5 kW at 400 V, Class 10, snaps onto 60 mm busbar. Active production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Motor Starters"],"specifications":{"Depth":"165 mm","Width":"45 mm","title":"3RA2125-1FH24-0FB4","Height":"260 mm","Upwards":"50 mm","Forwards":"20 mm","Backwards":"0 mm","Downwards":"10 mm","Trip Class":"CLASS 10","At The Side":"20 mm","Rated Value":"24 ... 24 V","description":"Load feeder fuseless, Direct-on-line starting 400 V AC, Size S0 3.50...5.00 A 24 V DC Spring-type terminal for 60 mm busbar systems (also fulfills type of coordination 1) Type of coordination 2, Iq = 150 kA 1 NO+1 NC (contactor) with diode combination plugged in at the front","During Storage":"-50 ... +80 °C","lifecycle_stage":"current","During Operation":"-20 ... +60 °C","During Transport":"-50 ... +80 °C","Fastening Method":"for snapping onto 60 mm busbar systems","Mounting Position":"vertical","PROFIsafe protocol":"No","Product Brand Name":"SIRIUS","Type Of Assignment":"2","Product Designation":"Direct (on-line) starter","Size Of Load Feeder":"S0","PROFINET IO protocol":"No","at 400 V rated value":"1 500 W","Design Of The Product":"for 60 mm busbars","For Main Current Circuit":"spring-loaded terminals","Temperature Compensation":"-20 ... +60 °C","Of The Supplied Contactor":"3RT2024-2FB40","Of The Supplied Link Module":"3RA2921-2AA00","Size Of The Circuit-Breaker":"S0","at AC-3 rated value maximum":"690 V","Design Of The Overload Release":"thermal (bimetallic)","Of The Supplied Busbar Adapter":"8US1251-5NT11","Design Of The Switching Contact":"electromechanical","Operating Frequency Rated Value":"50 ... 60 Hz","Design Of The Short-Circuit Trip":"magnetic","Of The Supplied Circuit-Breakers":"3RV2021-1FA25","degree of protection NEMA rating":"other","For Auxiliary And Control Circuit":"spring-loaded terminals","Product Extension Auxiliary Switch":"Yes","Relative Humidity During Operation":"10 ... 95 %","Surge Voltage Resistance Rated Value":"6 kV","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","protocol is supported AS-Interface protocol":"No","number of NC contacts for auxiliary contacts":"1","number of NO contacts for auxiliary contacts":"1","shock resistance according to IEC 60068-2-27":"6g / 11 ms","Type Of Voltage Of The Control Supply Voltage":"DC","at 400 V according to IEC 60947-4-1 rated value":"150 000 A","operational current at AC-3 at 400 V rated value":"3.6 A","Mechanical Service Life (Switching Cycles) Of Contactor Typical":"10 000 000","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"3.5 ... 5 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/a3cec7ea94393a4c44fad0d322a59844.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=552162&mlfb=3RA2125-1FH24-0FB4"},"ai":{"faq":[{"question":"What is 3RA2125-1FH24-0FB4's listed depth?","answer":"The depth is 165 mm, with a width of 45 mm and height of 260 mm. These dimensions include the busbar adapter and the supplied circuit breaker."},{"question":"What compliance documentation does Siemens provide for this starter?","answer":"The evidence does not list specific compliance certificates (RoHS, REACH, UL, IEC) for this order code. Standard Siemens SIRIUS documentation applies — confirm with your local Siemens support or request the declaration at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA2125-1FH24-0FB4","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/3RA2125-1FH24-0FB4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}