{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RK4320-3GQ51-1BA3","brand":"Siemens","brandSlug":"siemens","productSlug":"3RK4320-3GQ51-1BA3","canonicalUrl":"https://aoctrl.com/siemens/3RK4320-3GQ51-1BA3","factsUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3GQ51-1BA3","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS reversing starter, motor starter MCU for AS-Interface, 2.5 A AC-3 at 400 V, Class 10, IP54, DC control supply 20.4-26.4 V.","salesMarkdown":"## What is this part? The Siemens 3RK4320-3GQ51-1BA3 is a SIRIUS reversing motor starter designed as a motor starter MCU for AS-Interface communication, handling motor loads up to 2.5 A at AC-3 duty. It's a reversing starter, so it can switch a motor forward and reverse from the same unit — useful for conveyors, gates, or any application needing direction change without a separate contactor pair. Rated 2.5 A at AC-3 — that's the motor-switching current for squirrel-cage motors, not the resistive load rating. If your motor draws more than 2.5 A under full load, this starter won't hold. That's standard for standard-start induction motors; it won't nuisance-trip on normal starts but protects against sustained overload. Control supply is 20.4 to 26.4 V DC — a standard 24 VDC control bus works, but the tolerance means it stays held even if your DC rail sags a couple volts. Operating voltage range 340 to 440 V AC at 50/60 Hz covers 400 V nominal systems with typical tolerance. Won't work on a 480 V line without a transformer. IP54 enclosure keeps dust and splashing water out — fine for a dry control panel or a covered machine bay, but not for washdown zones. Ambient temperature range -25 to +50 °C covers most indoor plant floors without derating, though you'd want to check the thermal curve if mounting next to a heat source. Dimensions 245 mm wide × 215 mm high × 205 mm deep — measure your enclosure depth before committing; 205 mm is deeper than a typical contactor block. Communicates over AS-Interface, not PROFINET or PROFIBUS, so it needs an AS-i master in the network. Two digital inputs are built in for local sensors or pushbuttons. Includes a motor brake output for 400 V AC braking — if your application needs a mechanical brake, this unit handles the coil directly.","metaTitle":"Siemens 3RK4320-3GQ51-1BA3 SIRIUS Reversing Starter","metaDescription":"Siemens 3RK4320-3GQ51-1BA3 SIRIUS motor starter MCU for AS-Interface. Reversing starter, Class 10, 2.5 A at AC-3/400V. IP54, DC control. Current production.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"205 mm","Width":"245 mm","Height":"215 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":"IP54","PROFIBUS DP protocol":"No","Design Of The Product":"reversing starter","Number Of Digital Inputs":"2","Short Circuit Protection":"Yes","at AC at 400 V rated value":"2.5 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":"Yes","brake control with 500 V DC":"No","Type Of The Motor Protection":"bimetal","at AC-3 at 400 V rated value":"2.5 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 ... +50 °C","Product Component Motor Brake Output":"Yes","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":"0.8 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":"1.8 ... 2.5 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=421457&mlfb=3RK4320-3GQ51-1BA3","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3GQ51-1BA3/alternatives.json"},"ai":{"faq":[{"question":"Is 3RK4320-3GQ51-1BA3 a reversing starter?","answer":"Yes, it is a reversing starter — it switches motor direction forward and reverse from a single unit, designed as a motor starter MCU for AS-Interface."},{"question":"Where can I buy 3RK4320-3GQ51-1BA3 available via RFQ confirmation?","answer":"This part is sourced to order; availability and pricing are confirmed at quote time. Contact our sales team for current lead time and pricing."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RK4320-3GQ51-1BA3","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/3RK4320-3GQ51-1BA3 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}}