{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA2120-4CD27-0AP0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA2120-4CD27-0AP0","canonicalUrl":"https://aoctrl.com/siemens/3RA2120-4CD27-0AP0","factsUrl":"https://aoctrl.com/api/mcp/products/3RA2120-4CD27-0AP0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA2120-4CD27-0AP0 direct online motor starter, Size S0, 22 A AC-3 at 400 V, 690 V rated, Class 10 trip, for 60 mm busbar systems, screw terminals.","salesMarkdown":"## Active SIRIUS starter, built for 60 mm busbars The 3RA2120-4CD27-0AP0: It's designed specifically for snapping onto 60 mm busbar systems in vertical mounting — no separate DIN rail adapter or mounting plate needed, which saves panel depth and hardware cost. ## Motor-rating triangle: 22 A AC-3, 690 V, Class 10 Motor horsepower equivalents span 3 hp at 230 V, 7.5 hp at 200-230 V, and 15 hp at 460-480 V — useful when the BOM calls out NEMA ratings instead of FLA. ## Panel-fit envelope and clearance zones The footprint is 155 mm deep by 45 mm wide by 260 mm tall — narrow enough for a single 45 mm slot in a multi-starter lineup, but the 260 mm height needs vertical clearance in shallow enclosures. Required free space around the unit: 50 mm above, 20 mm forward, 10 mm below, 20 mm at the sides, and zero clearance at the back — the back surface sits flush against the busbar mount, so no rear breathing gap is needed. Operating temperature range is -20 to +60 °C, with storage and transport limits of -50 to +80 °C — the wider storage band matters for unheated warehouses in cold climates. ## Supplied components and wiring The starter ships as a factory-assembled unit including the 3RT2027-1AP00 contactor and the 3RA2921-1AA00 link module — no separate part ordering or assembly on site. Main circuit connections use screw-type terminals, which are field-friendly for stranded wire up to the rated cross-section; no special crimp tool or torque driver beyond a standard screwdriver. No PROFIsafe or PROFINET IO protocol support — this is a pure hardwired starter, not a fieldbus-integrated motor control center module. Control wiring is direct from the PLC or relay.","metaTitle":"Siemens 3RA2120-4CD27-0AP0 SIRIUS Motor Starter, 22 A AC-3","metaDescription":"Siemens 3RA2120-4CD27-0AP0 SIRIUS direct online motor starter, 22 A AC-3 at 400 V, Class 10, Size S0 for 60 mm busbars. Active production, available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Motor Starters"],"specifications":{"Depth":"155 mm","Width":"45 mm","title":"3RA2120-4CD27-0AP0","Height":"260 mm","Upwards":"50 mm","Forwards":"20 mm","at 50 Hz":"0.25","Backwards":"0 mm","Downwards":"10 mm","Trip Class":"CLASS 10","At The Side":"20 mm","Rated Value":"690 V","description":"Load feeder fuseless, Direct-on-line starting 400 V AC, Size S0 16...22 A 230 V AC 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)","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 230 V rated value":"3 hp","at 400 V rated value":"11 000 kW","at 480 V rated value":"22 A","at 50 Hz rated value":"230 ... 230 V","at 600 V rated value":"22 A","Design Of The Product":"for 60 mm busbars","For Main Current Circuit":"screw-type terminals","Temperature Compensation":"-20 ... +60 °C","at 110/120 V rated value":"1.5 hp","at 200/208 V rated value":"7.5 hp","at 220/230 V rated value":"7.5 hp","at 460/480 V rated value":"15 hp","Of The Supplied Contactor":"3RT2027-1AP00","Of The Supplied Link Module":"3RA2921-1AA00","Size Of The Circuit-Breaker":"S0","at AC-3 rated value maximum":"690 V","at AC-3 at 400 V rated value":"22 A","at AC-3e rated value maximum":"690 V","Substance Prohibitance (Date)":"10/01/2009","at AC-3e at 400 V rated value":"22 A","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 %","Without Load Current Share Typical":"9.8 W","Surge Voltage Resistance Rated Value":"6 kV","at AC in hot operating state per pole":"5.8 W","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","apparent holding power of magnet coil at AC":"9.8 VA","protocol is supported AS-Interface protocol":"No","with high demand rate according to SN 31920":"73 %","reference code according to IEC 81346-2:2019":"Q","shock resistance according to IEC 60068-2-27":"6g / 11 ms","Type Of Voltage Of The Control Supply Voltage":"AC","at 400 V according to IEC 60947-4-1 rated value":"150 000 A","Inductive Power Factor With The Holding Power Of The Coil":"0.25","Mechanical Service Life (Operating Cycles) Of Contactor Typical":"10 000 000","Response Value Current Of Instantaneous Short-Circuit Trip Unit":"286 A","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/4d1d1b210b8541971d1c7b05819f821b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=287805&mlfb=3RA2120-4CD27-0AP0"},"ai":{"faq":[{"question":"What are the key electrical ratings for this SIRIUS starter?","answer":"Motor horsepower equivalents are 3 hp at 230 V, 7.5 hp at 200-230 V, and 15 hp at 460-480 V."},{"question":"What physical clearances are needed around this starter?","answer":"Minimum free space: 50 mm above, 20 mm forward, 10 mm below, 20 mm at the sides, and zero clearance at the back. The overall dimensions are 155 mm deep by 45 mm wide by 260 mm tall."},{"question":"Does this starter include the contactor and link module?","answer":"Yes, it ships with the 3RT2027-1AP00 contactor and the 3RA2921-1AA00 link module pre-assembled — no separate ordering or field assembly of those components."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA2120-4CD27-0AP0","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/3RA2120-4CD27-0AP0 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}}