Model: ALR121-S00Module Type: Serial Communication Module (RS‑422/RS‑485, for FIO)Ports: 2 independent serial channels (software selectable RS‑422 or RS‑485)Communication Mode: Half‑duplex, start‑stop synchronizationBaud Rate: 300 bps to 115.2 kbps (supports 1200/2400/4800/9600/19200/38400 bps)Data Format: 7/8 data bits, 1/2 stop bits; parity: none/even/oddTransmission Code: ASCII/binaryMax Distance: 15 m (RS‑422 point‑to‑point); 1200 m total (RS‑485 multi‑drop)Isolation: 1500V DC channel‑to‑system isolationPower Supply: Backplane 24 V DCPower Consumption: Max 3.5 W (typical 2.8 W)Dimensions: 130 mm × 126.7 mm × 32.8 mmWeight: Approx. 0.3 kgMounting: AFV10/30/40, AFF50, ANB10/11, ANR10 racksOperating Temperature: 0°C to +55°CStorage Temperature: -20°C to +60°CHumidity: 10%–90% RH, non‑condensingCertifications: CE, UL, FM, CSA

Dual‑port design allows simultaneous connection to two serial devices, reducing cabling and retrofit costs.Software‑configurable RS‑422/RS‑485 supports point‑to‑point and multi‑drop topologies.1500V DC isolation protects the DCS from field electrical noise and faults.Supports Modbus RTU and subsystem communication protocols for flexible integration.Hot‑swappable for maintenance without system shutdown.Diagnostic LEDs for real‑time status monitoring and quick troubleshooting.Compact rack‑mount design with easy wiring and compatibility with standard Yokogawa racks.

S = Standard type0 = Non‑explosion proof0 = Basic configuration

Connects CENTUM VP DCS to RS‑422/RS‑485 devices: PLCs, Modbus RTU instruments, motor drives, and legacy serial equipment.Used in chemical plants, power stations, oil refineries, and metallurgical facilities for serial data exchange.Suitable for integrating field subsystems with FCS in process automation.