{"product_id":"alr121-s51-yokogawa-serial-communication-module","title":"ALR121-S51 Yokogawa Serial Communication Module","description":"\u003cp\u003eThe \u003cstrong\u003eYokogawa ALR121-S51\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eALR121\u003c\/strong\u003e Serial Communication Module, operates as a dedicated hardware component for half-duplex subsystem integration and data conversion within distributed control system (DCS) architectures.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cp\u003eThe ALR121 series utilizes explicit engineering suffixes to define hardware builds, communication interface variants, and hardware style revisions. Below is the technical breakdown for the \u003cstrong\u003eALR121-S51\u003c\/strong\u003e configuration:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eALR121\u003c\/strong\u003e: Core base model designator for the dual-port serial communication module.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e-S\u003c\/strong\u003e: Standard type construction baseline for standard industrial enclosure installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e5\u003c\/strong\u003e: Conformal coating designator for harsh environment protection against corrosive gases.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1\u003c\/strong\u003e: Style code indicating the physical hardware design revision or updated sub-component generation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eALR121-S51\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eYokogawa\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eJapan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.34 kg (Net) \/ 1.5 kg (Shipping)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003eStandard CENTUM series I\/O slot footprint size\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003eStandard industrial enclosure environmental parameters apply\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003eInternally derived via I\/O node backplane tracking\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eSerial Communication Modules\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Interface\u003c\/td\u003e\n\u003ctd\u003eRS-422 \/ RS-485 (4-wire system)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnection Method\u003c\/td\u003e\n\u003ctd\u003ePoint-to-point (RS-422) \/ Multipoint (RS-485)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Function\u003c\/td\u003e\n\u003ctd\u003eHalf-duplex tracking\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSynchronization Method\u003c\/td\u003e\n\u003ctd\u003eStart-stop synchronization (Asynchronous)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Speed\u003c\/td\u003e\n\u003ctd\u003e1200 \/ 2400 \/ 4800 \/ 9600 \/ 19200 \/ 38400 bps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnvironmental Protection\u003c\/td\u003e\n\u003ctd\u003eConformal coated board assembly\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eProcess Control System Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-20 mA HART Loop Protocol Network Arbitration\u003c\/strong\u003e The serial communication module establishes a deterministic hardware gateway over its dual 4-wire RS-422\/RS-485 channels, linking external subsystems like PLCs or specialized gas analyzers directly into the primary DCS architecture. It maps external variables into internal system register blocks, allowing digital subsystem data to coordinate alongside central 4-20 mA regulatory loops.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChannel-to-Channel Isolation Performance\u003c\/strong\u003e Ground loops and common-mode noise are suppressed via built-in electrical isolation barriers. This design prevents field-side electrical anomalies, lightning-induced surges, or localized short circuits on the long-distance RS-485 differential lines from migrating to adjacent communication paths or disrupting the internal backplane logic bus.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":47621296128190,"sku":"ALR121-S51","price":3000.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/screenshot_2026-06-11_15-31-20_43e06465-483f-4d79-a207-0a2421d1c2fe.png?v=1781164514","url":"https:\/\/www.autooiltech.com\/ar\/products\/alr121-s51-yokogawa-serial-communication-module","provider":"AutoOilTech Limited","version":"1.0","type":"link"}