{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RK4320-3KR51-0BA0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RK4320-3KR51-0BA0","canonicalUrl":"https://aoctrl.com/siemens/3RK4320-3KR51-0BA0","factsUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3KR51-0BA0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS motor starter MCU for AS-Interface, direct starter, 5 A at AC-3 400 V, Trip Class 10, IP55, 145 x 182 x 220 mm.","salesMarkdown":"It's a direct starter with electromechanical switching, rated 5 A at AC-3 400 V — that's the motor-load current it handles under full starting duty, not just resistive heating. ## Integration into a panel or line This unit mounts on a vertical surface with ±180° rotation possible and can tilt forward/backward ±22.5° — useful for tight enclosures where you need to angle the display or cable entry. The IP55 rating means it's dust-protected and handles water jets, so it's suited for washdown areas or outdoor cabinets where splash is a concern. It communicates over AS-Interface (the protocol is supported), not PROFINET or PROFIBUS DP, so verify your network master is AS-i capable. ## Supply and control voltage The control supply voltage is 20.4 to 26.4 V DC — that's the 24 V DC nominal range with tolerance. The main circuit operating voltage is 340 to 440 V AC, 50/60 Hz, covering 400 V line supplies. The 5 A AC-3 rating is the key figure for motor sizing: it's the current at 400 V under the heaviest switching category, so match it to your motor's full-load amps.","metaTitle":"Siemens 3RK4320-3KR51-0BA0 SIRIUS MCU, 5 A AC-3","metaDescription":"Siemens SIRIUS 3RK4320-3KR51-0BA0 motor starter MCU for AS-Interface, 5 A at AC-3 400 V, IP55, Trip Class 10. Sourced to order against an RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"145 mm","Width":"182 mm","title":"3RK4320-3KR51-0BA0","Height":"220 mm","Trip Class":"CLASS 10","description":"SIRIUS MCU motor starter Enclosure degree of protection IP55 plastic Communication AS-Interface electromechanically switching Short-circuit protection with circuit breaker DOL starter Brake without Performance class 5.00 A Motor circuit breaker with bi-metal thermal Manual operation without Connection power M screw connection Standard product","Type Of Voltage":"DC","lifecycle_stage":"current","Bus Communication":"Yes","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","PROFINET protocol":"No","Product Brand Name":"SIRIUS","Type Of Assignment":"1","Product Designation":"motor starter MCU for AS-Interface","protection class IP":"IP55","PROFIBUS DP protocol":"No","Design Of The Product":"direct starter","Number Of Digital Inputs":"0","Short Circuit Protection":"Yes","at AC at 400 V rated value":"5 A","brake control with 24 V DC":"No","Operating Frequency Minimum":"80 1/h","brake control with 180 V DC":"No","brake control with 400 V AC":"No","brake control with 500 V DC":"No","Type Of The Motor Protection":"bimetal","at AC-3 at 400 V rated value":"5 A","Operating Voltage Rated Value":"340 ... 440 V","Substance Prohibitance (Date)":"05/01/2012","Design Of The Switching Contact":"electromechanical","Operating Frequency 1 Rated Value":"50 Hz","Operating Frequency 2 Rated Value":"60 Hz","Design Of Short-Circuit Protection":"circuit-breakers","Ambient Temperature During Operation":"-25 ... +35 °C","Product Component Motor Brake Output":"No","Type Of Voltage Of The Supply Voltage":"DC","reference code according to IEC 81346-2":"Q","Number Of Poles For Main Current Circuit":"3","control supply voltage at DC rated value":"20.4 ... 26.4 V","with low demand rate according to SN 31920":"50 %","protocol is supported AS-Interface protocol":"Yes","with high demand rate according to SN 31920":"75 %","operating power at AC-3 at 400 V rated value":"1.5 kW","Product Extension Braking Module For Brake Control":"No","Relative Negative Tolerance Of The Operating Frequency":"-10 %","Relative Positive Tolerance Of The Operating Frequency":"10 %","Type Of Electrical Connection For Main Current Circuit":"screw-type terminals","breaking capacity maximum short-circuit current (Icu) at 400 V rated value":"50 000 A","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/d477e2670c1c605bf02dc49610d2264c.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=125736&mlfb=3RK4320-3KR51-0BA0"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RK4320-3KR51-0BA0","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/3RK4320-3KR51-0BA0 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}}