Features:
- Dual serial ports: two RS-422/RS-485 communication interfaces
- Flexible links: point-to-point RS-422 and multipoint RS-485 operation
- Long-distance communication: up to 1200 m total extended length
The ALR121-S50 S1 configuration is a standard module without explosion protection and with the basic environmental option.
It connects a field control station to external subsystems through half-duplex serial communication with configurable protocol settings.
Confirm the subsystem protocol, baud rate, cable type, and supported host unit before installation.
Availability is subject to Apter Power inventory and sourcing confirmation.
Verified resources for Yokogawa ALR121-S50 S1:
Yokogawa ALR121-S50 S1 Serial Communication Module Specifications
General
- ManufacturerYokogawa
- ModelALR121-S50 S1
- ConditionNew and factory sealed
- Product FamilyN-IO/FIO Serial Communication Modules
- RS-422: point-to-point connection for a direct subsystem link
- RS-485: multipoint connection across the documented bus length
- Transfer mode: half-duplex with start-stop synchronization
- Data format: ASCII or binary with selectable character, stop-bit, and parity settings
- Supported hosts: documented ANB, AFV, and A2FV node or control units
- Subsystem access: supports documented FA-M3, Modbus, MELSEC-A, YS, SLC500, and PLC-5 functions
- Port settings: both ports use the same selected communication function
- Engineering: configure communication definitions through the supported CENTUM VP builder function
- Module pair: install two identical ALR121 modules in adjacent even and odd slots
- Control transfer: communication switches to the standby module after a detected module or subsystem fault
- Port behavior: both ports switch control and standby sides together
- Restriction: one-shot write cannot be used with dual-redundant communication