{"product_id":"yokogawa-alr121-s50-rs-422-rs-485-serial-communication-module","title":"Yokogawa ALR121-S50 RS-422\/RS-485 Serial Communication Module","description":"\u003ch3 class=\"\"\u003eProduct Overview\u003c\/h3\u003e\n\u003cp\u003e\u003cspan class=\"\"\u003eThe Yokogawa ALR121-S50 is a high-reliability Serial Communication Module engineered for the CENTUM VP Distributed Control System (DCS) and the ProSafe-RS Safety Instrumented System (SIS).\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eThis module functions as a critical communication bridge,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eallowing Safety Control Stations (SCS) to interface with external Modbus master devices or subsystems via RS-422\/RS-485 serial links.\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eIt is specifically designed to facilitate data transparency without compromising the functional safety of the overall system.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan class=\"\"\u003eSupporting SIL3 safety integrity levels in accordance with IEC 61508,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003ethe ALR121-S50 ensures that process data is exchanged securely and accurately.\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eIts architecture is optimized for mission-critical applications such as Emergency Shutdown (ESD) systems,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eFire and Gas (F\u0026amp;G) systems,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eand Burner Management Systems (BMS),\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003ewhere both data reporting and safety compliance are paramount.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 class=\"\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eManufacturer:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eYokogawa\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eModel Number:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eALR121-S50\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eCommunication Interface:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eRS-422 \/ RS-485 (Serial)\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eProtocol Support:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eModbus Slave\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eNumber of Ports:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e2 independent ports\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eSafety Integrity Level:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eSIL3 certified (when used with ProSafe-RS)\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eData Rate:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e300 bps to 115.\u003c\/span\u003e\u003cspan class=\"\"\u003e2 kbps\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eIsolation:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eGalvanic isolation between field signals and internal circuitry\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eOperating Temperature:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e-20°C to +70°C\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eWeight:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e0.\u003c\/span\u003e\u003cspan class=\"\"\u003e3 kg\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eDimensions:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e32.\u003c\/span\u003e\u003cspan class=\"\"\u003e8 mm x 141.\u003c\/span\u003e\u003cspan class=\"\"\u003e2 mm x 130 mm\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eMounting:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eCompact FIO (Field Interface Orbus) architecture\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 class=\"\"\u003eKey Operational Features\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eDual-Port Redundancy:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eProvides two ports per module to support redundant cabling and fault-tolerant communication architectures,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eensuring continuous availability even if one link fails.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eSIL3 Certified Connectivity:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eMaintains the highest level of safety integrity while allowing external Modbus devices to read safety-related data for monitoring or plant-wide integration.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eElectromagnetic Compatibility:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eFeatures advanced electrical isolation to prevent ground loops and shield the safety network from electromagnetic interference (EMI) typical in heavy industrial environments.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eReal-Time Diagnostics:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eEquipped with front-panel LED indicators (RDY,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eHRD,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eTX,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eRX) for immediate visual confirmation of module health and data transmission status.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eIntegrated Configuration:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eFully supported within the Yokogawa engineering environment,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eenabling streamlined setup of Modbus mapping and communication parameters through standard software tools.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong class=\"\"\u003eRobust Environmental Build:\u003c\/strong\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eEngineered for longevity in harsh conditions,\u003c\/span\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003eincluding high vibration and temperature fluctuations common in oil \u0026amp; gas and petrochemical facilities.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":45519063580845,"sku":"ALR121-S50","price":99.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0733\/1613\/9181\/files\/yokogawa-alr121-s50-serial-communication-module-4oamzrre4ww.jpg?v=1766986023","url":"https:\/\/www.maxwellplc.com\/products\/yokogawa-alr121-s50-rs-422-rs-485-serial-communication-module","provider":"Maxwell PLC Ltd","version":"1.0","type":"link"}