{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RK4320-3DQ54-1BA3","brand":"Siemens","brandSlug":"siemens","productSlug":"3RK4320-3DQ54-1BA3","canonicalUrl":"https://aoctrl.com/siemens/3RK4320-3DQ54-1BA3","factsUrl":"https://aoctrl.com/api/mcp/products/3RK4320-3DQ54-1BA3","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RK4320-3DQ54-1BA3 motor starter MCU for AS-Interface, reversing starter, 1.25 A at 400 V AC-3, CLASS 10 bimetal overload, IP54, 205 mm depth.","salesMarkdown":"## Active production — what it means for your BOM line The 3RK4320-3DQ54-1BA3: No stock-holding claim — quoted per BOM. ## What the 1.25 A AC-3 rating and CLASS 10 trip mean for motor starting The same 1.25 A appears at 400 V for general AC use, so the motor full-load current must not exceed this figure. The bimetal design provides thermal memory: it tracks the motor's heating between starts. Operating frequency is rated 80 operations per hour — this sets the thermal cycling limit for the starter contacts and bimetal. Above 80 1/h, the internal temperature rise accumulates and may reduce contact life or cause premature overload trips. ## Mounting, enclosure fit, and wiring constraints The starter measures 205 mm deep, 245 mm wide, and 215 mm high. Plan for a 250 mm wide DIN-rail section inside the enclosure — the 245 mm width leaves 5 mm clearance on each side for rail-end anchors and wiring channels. This means you can orient the starter to fit tight enclosures or angled sub-panels, but the IP54 seal assumes the gasket is compressed evenly — avoid skewing the mounting screws. IP54 rating means dust-protected and splash-resistant — adequate for control cabinets in light industrial environments, but not for washdown zones. If the enclosure is in a wet area, the starter itself needs a sealed cabinet door. ## AS-Interface bus integration and control supply This motor starter communicates via AS-Interface protocol — no PROFIBUS DP or PROFINET support. The AS-i bus carries both the control signals and the 24 V DC supply; the control supply voltage range is 20.4…26.4 V DC, matching the standard AS-i power supply output. Two digital inputs are available on the starter for local sensors or pushbuttons — these are read over the AS-i bus. The reversing starter design means it has two contactors (forward/reverse) with mechanical interlock, wired internally. A motor brake output with 400 V AC control is integrated — this is for holding brakes on vertical-axis motors. The brake coil is switched directly from the starter; no external brake rectifier needed when the brake is rated 400 V AC. ## Compliance and substance prohibitions The substance prohibitance date is 05/01/2012 — this aligns with RoHS compliance milestones. The starter meets the substance restrictions in effect from that date; REACH and WEEE documentation should be available from Siemens on request.","metaTitle":"Siemens 3RK4320-3DQ54-1BA3 SIRIUS Motor Starter, 1.25 A","metaDescription":"Siemens 3RK4320-3DQ54-1BA3 SIRIUS motor starter MCU for AS-Interface, reversing starter, 1.25 A at 400 V AC-3, CLASS 10 bimetal protection, IP54.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"205 mm","Width":"245 mm","title":"3RK4320-3DQ54-1BA3","Height":"215 mm","Trip Class":"CLASS 10","description":"SIRIUS MCU motor starter Enclosure degree of protection IP54 metal Communication AS-Interface electromechanically switching Short-circuit protection with circuit breaker Reversing starter Brake 400 V AC (internal) Performance class 1.25 A Motor circuit breaker with bi-metal thermal Rotary operating mechanism gray/black 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":"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":"1.25 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":"1.25 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":"0.4 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":"0.9 ... 1.25 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/6ef5e5a499b5b600447b7e41dd8fc6cb.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=48768&mlfb=3RK4320-3DQ54-1BA3"},"ai":{"faq":[{"question":"What is the 3RK4320-3DQ54-1BA3 rated current at 400 V AC-3?","answer":"The motor full-load current must stay at or below this value."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RK4320-3DQ54-1BA3","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/3RK4320-3DQ54-1BA3 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}}