{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RK4320-3CR51-1BA0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RK4320-3CR51-1BA0","canonicalUrl":"https://aoctrl.com/siemens/3RK4320-3CR51-1BA0","factsUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3CR51-1BA0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS motor starter MCU for AS-Interface, reversing starter, 1 A AC-3 at 400 V, Class 10, IP55, 145 x 182 x 220 mm.","salesMarkdown":"## SIRIUS reversing motor starter for AS-Interface It integrates motor protection, reversing contactors, and short-circuit protection into one IP55-rated enclosure, saving panel space and wiring time on conveyor, material handling, and small drive applications. The Class 10 bimetal overload relay protects against sustained overcurrent — typical for motor start-up profiles under 10 seconds. Operating voltage is 340 to 440 V AC, 50/60 Hz, with a control supply of 20.4 to 26.4 V DC. The unit is a reversing starter, meaning it can change motor rotation direction without external contactors — a common requirement for bidirectional conveyors or actuator positioning. Dimensions are 145 mm deep, 182 mm wide, and 220 mm high — roughly the footprint of a small distribution block, not a full motor control center bucket. The IP55 rating means it handles dust and low-pressure water jets — suitable for installation in washdown areas or outdoor cabinets without a separate enclosure. Short-circuit protection is integrated via circuit breakers, so no upstream fusing is required for the starter itself. AS-Interface is the only bus protocol supported — no PROFINET or PROFIBUS DP on this variant. The single AS-i cable carries both power and communication, reducing field wiring to a two-wire loop.","metaTitle":"Siemens 3RK4320-3CR51-1BA0 SIRIUS motor starter MCU, AS-i","metaDescription":"Siemens SIRIUS 3RK4320-3CR51-1BA0 reversing motor starter MCU for AS-Interface, 1 A AC-3 at 400 V, Class 10, IP55, current production, available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"145 mm","Width":"182 mm","Height":"220 mm","Trip Class":"CLASS 10","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":"reversing starter","Number Of Digital Inputs":"0","Short Circuit Protection":"Yes","at AC at 400 V rated value":"1 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":"1 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":"0.3 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":"0.7 ... 1 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=4293&mlfb=3RK4320-3CR51-1BA0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3CR51-1BA0/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RK4320-3CR51-1BA0?","answer":"The 3RK4320-3CR51-1BA0 is sourced to order against an RFQ through independent distribution channels. Submit a quote request for current availability and pricing."},{"question":"Does 3RK4320-3CR51-1BA0 support AS-Interface communication?","answer":"Yes, AS-Interface (AS-i) is the supported bus protocol. It does not support PROFINET or PROFIBUS DP."},{"question":"What is the rated current of the 3RK4320-3CR51-1BA0?","answer":"The AC-3 rated current at 400 V is 1 A — suitable for small motor loads up to that current under full-load switching."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RK4320-3CR51-1BA0","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/3RK4320-3CR51-1BA0 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}