{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA2120-1KA24-0AP6","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA2120-1KA24-0AP6","canonicalUrl":"https://aoctrl.com/siemens/3RA2120-1KA24-0AP6","factsUrl":"https://aoctrl.com/api/mcp/products/3RA2120-1KA24-0AP6","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA2120-1KA24-0AP6 non-fused direct starter, size S0, 5.5 kW at 400 V, CLASS 10 thermal bimetallic overload, 45 x 193.1 x 97.1 mm.","salesMarkdown":"## What this SIRIUS starter delivers The 3RA2120-1KA24-0AP6: It's a direct starter design, meaning it applies full line voltage to the motor terminals on start — no reduced-voltage ramp. The overload release is thermal bimetallic, so it tracks the motor's heating curve by sensing current through a bimetal strip that bends to trip the contactor on sustained overcurrent. ## CLASS 10 trip — why it matters for your motor That's the standard for standard-duty induction motors — pumps, fans, compressors — where the starting current decays within a few seconds. If you're protecting a high-inertia load like a centrifuge or a large flywheel that takes longer to accelerate, you'd want a CLASS 20 or CLASS 30 trip curve instead; this starter won't hold through that extended start. The thermal bimetallic design is ambient-compensated across the -20 to +60 °C operating range, so the trip point stays consistent whether the panel sits in a conditioned room or a hot factory floor. ## Panel fit: dimensions and mounting The starter measures 45 mm wide by 193.1 mm tall by 97.1 mm deep — that's a single 45 mm module width on a DIN rail, so it occupies one position in a standard 19-inch subrack. Snap it onto the DIN rail or screw-mount it with the additional push-in lug; the mounting position must be vertical. Clearance requirements: allow 30 mm above, 10 mm below, 10 mm forward, 9 mm to the side, and 0 mm backward. The zero backward clearance means it can sit flush against a back panel or a busbar — useful when packing multiple starters into a tight enclosure. ## Sourcing and lifecycle — current production The starter ships as a factory-assembled unit containing the 3RT2024-1AP60 contactor and the 3RA2921-1AA00 link module. The circuit-breaker size is S00, which is one frame size smaller than the S0 feeder — that's the standard SIRIUS pairing for this rating.","metaTitle":"Siemens 3RA2120-1KA24-0AP6 SIRIUS Motor Starter","metaDescription":"Siemens 3RA2120-1KA24-0AP6 SIRIUS non-fused motor starter, size S0, 5.5 kW at 400 V, CLASS 10 thermal overload. Current production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"97.1 mm","Width":"45 mm","title":"3RA2120-1KA24-0AP6","Height":"193.1 mm","Upwards":"30 mm","Forwards":"10 mm","Backwards":"0 mm","Downwards":"10 mm","Trip Class":"CLASS 10","At The Side":"9 mm","Rated Value":"690 V","description":"Fuseless motor starter Direct start 600VAC Size S0 9-12.5 Amp 220/240VAC 50/60HZ screw connection For screw mounting Or 35 mm rail-mounting Type of coordination 2 IQ = 150 KA Also full fills type Of coordination 1 1NO+1NC (contactor)","During Storage":"-50 ... +80 °C","lifecycle_stage":"current","During Operation":"-20 ... +60 °C","During Transport":"-55 ... +80 °C","Fastening Method":"Snap-mounted to DIN rail or screw-mounted with additional push-in lug","Mounting Position":"vertical","Product Brand Name":"SIRIUS","Type Of Assignment":"2","Degree Of Pollution":"3","Product Designation":"non-fused motor starter 3RA2","Size Of Load Feeder":"S0","at 230 V rated value":"2 hp","at 400 V rated value":"5 500 W","at 480 V rated value":"11 A","at 50 Hz rated value":"176 ... 242 V","at 500 V rated value":"7 500 W","at 60 Hz rated value":"192 ... 264 V","at 600 V rated value":"11 A","Design Of The Product":"direct starter","at 110/120 V rated value":"0.5 hp","at 200/208 V rated value":"3 hp","at 220/230 V rated value":"3 hp","at 460/480 V rated value":"7.5 hp","at 575/600 V rated value":"10 hp","Of The Supplied Contactor":"3RT2024-1AP60","Of The Supplied Link Module":"3RA2921-1AA00","Size Of The Circuit-Breaker":"S00","at AC-3 rated value maximum":"690 V","Design Of The Overload Release":"thermal (bimetallic)","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":"3RV2011-1KA10","Product Extension Auxiliary Switch":"Yes","Surge Voltage Resistance Rated Value":"6 kV","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","apparent holding power of magnet coil at AC":"7.2 VA","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","at 400 V according to IEC 60947-4-1 rated value":"153 000 A","operational current at AC-3 at 400 V rated value":"11.5 A","Type Of Electrical Connection For Main Current Circuit":"screw-type terminals","Inductive Power Factor With The Holding Power Of The Coil":"0.28","Mechanical Service Life (Operating Cycles) Of Contactor Typical":"10 000 000","Response Value Current Of Instantaneous Short-Circuit Trip Unit":"162.5 A","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Type Of Connectable Conductor Cross-Sections For Main Contacts Stranded":"1 ... 10 mm², 2x (2.5 ... 6 mm²)","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"9 ... 12.5 A","Connectable Conductor Cross-Section For Main Contacts Finely Stranded With Core End Processing":"1 ... 6 mm²"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/7976098b14d164809c1a09c3884e0b95.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=346939&mlfb=3RA2120-1KA24-0AP6"},"ai":{"faq":[{"question":"What motor power can 3RA2120-1KA24-0AP6 handle at 400 V?","answer":"At 400 V AC-3 duty, it's rated for 5.5 kW (7.5 hp). At 460/480 V it handles 7.5 hp, and at 575/600 V it's rated for 10 hp. The maximum AC-3 operating voltage is 690 V."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA2120-1KA24-0AP6","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/3RA2120-1KA24-0AP6 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}}