Yokogawa ALR121-S00 S1 ProSafe-RS Communication Module
The Yokogawa ALR121-S00 S1, also cataloged as the ALR121-S00 Communication Module, is configured for interference-free serial communication within safety-instrumented platforms, providing direct physical/electrical execution.
Suffix Breakdown & Model Matrix
- ALR121: Base model designating the dual-port serial communication module supporting RS-422 and RS-485 interfaces.
- -S00: Standard suffix configuration specifying base hardware execution without hazardous location special coatings or extended temperature tier variations.
- S1: Style code designation representing the hardware manufacturing revision level for system bus compatibility.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | ALR121-S00 S1 |
| Brand | Yokogawa |
| Origin | Japan |
| Weight | Approx. 0.34 kg |
| Dimensions | Standard Yokogawa module form factor |
| Operating Temp | 0 to 55 deg C |
| Power Consumption | 0.5 A |
| Interface | RS-422 / RS-485 (4-wire system) |
| Transmission Speed | 1200 / 2400 / 4800 / 9600 / 19200 / 38400 bps |
| Connection Type | D-sub 9-pin and M4 screw terminal block |
Channel-to-Channel Isolation and Serial Protocols
The Yokogawa ALR121-S00 S1 module incorporates galvanic isolation to ensure its serial communication loops remain entirely interference-free relative to critical safety loops. Operating via half-duplex transmission protocols with start-stop synchronization, the module handles binary data framing with configurable parity and fixed 8-bit character lengths. Signal paths are engineered to prevent common-mode voltage propagation and ground loops across connected RS-422 point-to-point links and RS-485 multipoint networks.
Frequently Asked Questions
Q: Does the installation of the ALR121-S00 S1 module impact the integrity of active safety loops?
A: No. The module is structurally classified as an interference-free component designed with galvanic separation to ensure that subsystem and Modbus data traffic induces no interference with the core safety loop execution.
Q: What are the fixed character and stop bit parameters when utilizing Modbus slave functions?
A: Character length is fixed at 8 bits, and the stop bit length is governed by the selected configuration, with subsystem communication enforcing a strict 1-bit stop bit length.
Field Installation Guidelines
- Ensure slot power is isolated on the parent node before inserting or extracting the ALR121-S00 S1 module.
- Terminate incoming RS-485 or RS-422 signal lines securely using either the D-sub 9-pin connectors or the M4 clamping terminal screws.
- Connect cable shield drains to the designated panel ground bar to maintain electromagnetic compatibility.
- Verify that line termination resistors are correctly matched to the characteristic impedance of the field communication cable run.
- Route low-voltage serial communication wiring through segregated cable trays away from high-power alternating current distribution lines.
Yokogawa ALR121-S00 S1 ProSafe-RS Communication Module
Yokogawa ALR121-S00 S1 ProSafe-RS Communication Module
The Yokogawa ALR121-S00 S1, also cataloged as the ALR121-S00 Communication Module, is configured for interference-free serial communication within safety-instrumented platforms, providing direct physical/electrical execution.
Suffix Breakdown & Model Matrix
- ALR121: Base model designating the dual-port serial communication module supporting RS-422 and RS-485 interfaces.
- -S00: Standard suffix configuration specifying base hardware execution without hazardous location special coatings or extended temperature tier variations.
- S1: Style code designation representing the hardware manufacturing revision level for system bus compatibility.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | ALR121-S00 S1 |
| Brand | Yokogawa |
| Origin | Japan |
| Weight | Approx. 0.34 kg |
| Dimensions | Standard Yokogawa module form factor |
| Operating Temp | 0 to 55 deg C |
| Power Consumption | 0.5 A |
| Interface | RS-422 / RS-485 (4-wire system) |
| Transmission Speed | 1200 / 2400 / 4800 / 9600 / 19200 / 38400 bps |
| Connection Type | D-sub 9-pin and M4 screw terminal block |
Channel-to-Channel Isolation and Serial Protocols
The Yokogawa ALR121-S00 S1 module incorporates galvanic isolation to ensure its serial communication loops remain entirely interference-free relative to critical safety loops. Operating via half-duplex transmission protocols with start-stop synchronization, the module handles binary data framing with configurable parity and fixed 8-bit character lengths. Signal paths are engineered to prevent common-mode voltage propagation and ground loops across connected RS-422 point-to-point links and RS-485 multipoint networks.
Frequently Asked Questions
Q: Does the installation of the ALR121-S00 S1 module impact the integrity of active safety loops?
A: No. The module is structurally classified as an interference-free component designed with galvanic separation to ensure that subsystem and Modbus data traffic induces no interference with the core safety loop execution.
Q: What are the fixed character and stop bit parameters when utilizing Modbus slave functions?
A: Character length is fixed at 8 bits, and the stop bit length is governed by the selected configuration, with subsystem communication enforcing a strict 1-bit stop bit length.
Field Installation Guidelines
- Ensure slot power is isolated on the parent node before inserting or extracting the ALR121-S00 S1 module.
- Terminate incoming RS-485 or RS-422 signal lines securely using either the D-sub 9-pin connectors or the M4 clamping terminal screws.
- Connect cable shield drains to the designated panel ground bar to maintain electromagnetic compatibility.
- Verify that line termination resistors are correctly matched to the characteristic impedance of the field communication cable run.
- Route low-voltage serial communication wiring through segregated cable trays away from high-power alternating current distribution lines.
