{"product_id":"yokogawa-alr121-s01-centum-vp-serial-communication-module","title":"Yokogawa ALR121-S01 CENTUM VP Serial Communication Module","description":"\u003ch3\u003eProduct Overview\u003c\/h3\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eYokogawa ALR121-S01\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eserves as a high-performance serial communication interface for the CENTUM VP and CS 3000 Distributed Control Systems (DCS). This module provides two independent ports supporting RS-422 and RS-485 standards, allowing the Field Control Unit (FCU) to manage long-distance data exchange with third-party subsystems. Whether connecting to Variable Frequency Drives (VFDs), PLCs, or smart analytical instruments, the ALR121-S01 ensures deterministic integration into the primary control environment. We supply this unit as\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e100% Brand New and Original\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eto guarantee maximum reliability for your plant’s critical communication loops.\u003c\/p\u003e\n\u003ch3\u003ePart Number Breakdown\u003c\/h3\u003e\n\u003cp\u003eThe ALR121-S01 utilizes a specific suffix logic to define its hardware revision and functional capabilities:\u003c\/p\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr class=\"firstRow\"\u003e\n\u003ctd\u003e\u003cstrong\u003eSuffix Code\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eTechnical Definition\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eALR121\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eSerial Communication Module (RS-422\/RS-485 Type)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003e-S\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eStandard Type Hardware\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003e0\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eFixed Identifier\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003e1\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eBasic Functional Type (Revision 1)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cp\u003eThe ALR121-S01 maintains stable data throughput across long cable runs in high-interference environments.\u003c\/p\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCommunication Interface:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eRS-422\/RS-485 (2 ports).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eTransmission Speed:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e300 bps to 115.2 kbps.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eConnection Type:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eSupports 2-wire or 4-wire configurations (protocol dependent).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eMaximum Distance:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e1,200 meters (approx. 4,000 feet) without repeaters.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eIsolation:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eHigh-grade galvanic isolation protects internal DCS circuitry.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003ePower Consumption:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e0.5 A at 5V DC (supplied via backplane).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCondition:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eGuaranteed 100% Brand New Original.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eEngineering Advantages\u003c\/h3\u003e\n\u003cp\u003eThe ALR121-S01 addresses the core challenges of multi-vendor subsystem integration:\u003c\/p\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSuperior Noise Immunity:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe differential signaling inherent in RS-422\/485 protocols allows the ALR121-S01 to reject electromagnetic interference (EMI). This makes it the ideal choice for communication paths that run alongside high-voltage power cables or near heavy industrial machinery.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eMulti-Drop Network Capability:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eIn RS-485 mode, this module supports multi-drop configurations. This allows engineers to daisy-chain multiple slave devices to a single port, significantly reducing the cost of wiring and maximizing the utilization of each module slot.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eOffloaded Protocol Management:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe module features an internal processor that handles the serial protocol stack independently. This design prevents communication tasks from consuming the Field Control Unit’s (FCU) CPU cycles, maintaining the speed and determinism of your primary control loops.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSeamless Redundancy:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eYou can install two ALR121-S01 modules in a duplexed configuration. If the active module detects a hardware failure or a cable break, the standby unit assumes control of the serial link instantly, ensuring that critical subsystem data remains available to the operator.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFAQs\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCan the ALR121-S01 communicate with Modbus RTU devices?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The ALR121-S01 provides the physical RS-485 hardware layer. When configured with the appropriate communication drivers in the CENTUM software, it seamlessly interfaces with any Modbus RTU slave device.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the difference between the S01 and S00 versions?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe S01 designation typically identifies a specific functional revision level required for compatibility with certain software versions of CENTUM VP. We recommend verifying your system's hardware profile to ensure the S01 matches your project's configuration database.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eHow do I handle termination resistors for this module?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor RS-422\/485 networks, you must install a 120-ohm termination resistor at both ends of the segment to prevent signal reflection. The ALR121-S01 allows for easy termination at the module end via the standard connection procedures.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this product come in original factory packaging?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAbsolutely. Every ALR121-S01 we ship is\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e100% Brand New and Original\u003c\/strong\u003e, arriving in its authentic Yokogawa box with factory seals and full serial number traceability.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":52824129831221,"sku":"ALR121-S01","price":66.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0973\/7630\/5461\/files\/ALR121-S00_8034e961-dbae-4d8d-97b6-c070d36b6eca.png?v=1778037898","url":"https:\/\/www.5gplc.com\/products\/yokogawa-alr121-s01-centum-vp-serial-communication-module","provider":"High Five PLC Solution Limited","version":"1.0","type":"link"}