{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA2120-4CD27-0FB4","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA2120-4CD27-0FB4","canonicalUrl":"https://aoctrl.com/siemens/3RA2120-4CD27-0FB4","factsUrl":"https://aoctrl.com/api/mcp/products/3RA2120-4CD27-0FB4","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA2120-4CD27-0FB4 direct online starter, S0 size, 11 kW at 400 V AC-3, Class 10, 24 V DC coil, for 60 mm busbar systems, screw terminals.","salesMarkdown":"## What ships in the carton — a complete SIRIUS feeder The 3RA2120-4CD27-0FB4: This is a factory-assembled direct-on-line starter, S0 size, built around the 3RT2027-1FB40 contactor and a thermal bimetallic overload relay with magnetic short-circuit trip. The kit includes the 3RV2021-4CA10 circuit-breaker, the 3RA2921-1BA00 link module, and the 8US1251-5NT10 busbar adapter — everything needed to snap onto a 60 mm busbar system and land the motor feeder in one assembly. No loose pieces to order separately: the contactor, overload relay, breaker, link module, and busbar adapter all arrive as one order code. ## Motor rating and trip coordination Rated 11 kW at 400 V AC-3, maximum operating voltage 690 V, 50/60 Hz — this covers the standard European 400 V motor frame up to 11 kW and can handle 690 V industrial networks where the line-to-line voltage is higher. ## Mounting and panel integration Designed for snapping onto 60 mm busbar systems — the busbar adapter (included) clips the starter directly onto the busbar, eliminating separate DIN-rail mounting and busbar wiring for the main circuit. Dimensions: 260 mm high, 45 mm wide, 165 mm deep — the 45 mm width (S0 size) keeps the feeder footprint narrow, allowing multiple starters side-by-side on the same busbar run. Mounting position is vertical only; clearance requirements: 50 mm upwards, 20 mm forwards, 10 mm downwards, 20 mm at the side, zero backwards — plan the enclosure depth and ventilation gaps accordingly. ## Lifecycle and sourcing Current production — this is an active SIRIUS catalog item, not a legacy or phased-out code.","metaTitle":"Siemens 3RA2120-4CD27-0FB4 SIRIUS Direct Starter","metaDescription":"Siemens 3RA2120-4CD27-0FB4 SIRIUS direct online starter, 11 kW at 400 V AC-3, Class 10, S0 size, for 60 mm busbars. Current 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":"3RA2120-4CD27-0FB4","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 16...22 A 24 V DC screw 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":"11 000 W","Design Of The Product":"for 60 mm busbars","For Main Current Circuit":"screw-type terminals","Temperature Compensation":"-20 ... +60 °C","Of The Supplied Contactor":"3RT2027-1FB40","Of The Supplied Link Module":"3RA2921-1BA00","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":"8US1251-5NT10","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":"3RV2021-4CA10","degree of protection NEMA rating":"other","For Auxiliary And Control Circuit":"screw-type terminals","Product Extension Auxiliary Switch":"Yes","Relative Humidity During Operation":"10 ... 95 %","holding power of magnet coil at DC":"5.9 W","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","with high demand rate according to SN 31920":"73 %","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":"22 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":"16 ... 22 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/77b1b0035ac8d85294c28ee344d3131b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=283798&mlfb=3RA2120-4CD27-0FB4"},"ai":{"faq":[{"question":"What is the motor rating of 3RA2120-4CD27-0FB4?","answer":"The trip class is Class 10."},{"question":"What components are included with 3RA2120-4CD27-0FB4?","answer":"The kit includes the 3RT2027-1FB40 contactor, 3RV2021-4CA10 circuit-breaker, 3RA2921-1BA00 link module, and 8US1251-5NT10 busbar adapter — a complete feeder assembly for 60 mm busbars."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA2120-4CD27-0FB4","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/3RA2120-4CD27-0FB4 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}}