Product Details
Product Overview
The Yokogawa ALR121-S50 functions as a core serial communication module for the CENTUM integrated production control system. It provides two independent channels for RS-422 or RS-485 serial data exchange, connecting external subsystems such as PLCs, analyzers, or power meters to the field control station. We supply this module as 100% Brand New and Original, ensuring optimal data throughput and integration integrity for your control architecture.
Part Number Breakdown
| Code | Specification | Description |
| ALR121 | Model | Serial Communication Module (RS-422/RS-485, 2 ports) |
| -S | Type | Standard Type |
| 5 | Protection | With no explosion protection |
| 0 | Version | Basic type hardware revision |
Technical Specifications
| Feature | Specification |
| Interface | RS-422/RS-485 |
| Communication Mode | Half-duplex |
| Transmission Speed | 1200 to 38400 bps |
| Synchronization | Start-stop synchronization |
| Code Structure | ASCII / Binary |
| Current Consumption | 0.5 A |
| Dimensions | 3.28 cm x 14.29 cm x 13 cm |
| Weight | 0.3 kg |
Engineering Advantages
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Flexible Topology: The module supports point-to-point connections for RS-422 and multipoint daisy-chain configurations for RS-485. This versatility allows engineers to deploy multiple field devices on a single physical bus, reducing cabling complexity.
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Variable Baud Rate Control: Users select from a broad range of transmission speeds (up to 38400 bps), allowing precise matching with the latency requirements of legacy third-party subsystems.
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Compact Physical Footprint: The module measures only 3.28 cm in width, optimizing valuable cabinet space in high-density rack environments. Its slim design promotes better airflow around adjacent I/O modules, preventing localized hot spots.
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Simplified Integration: The module utilizes standard start-stop synchronization, ensuring seamless handshake protocols with most industrial sensors and actuators without requiring custom middleware.
FAQs
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Can I connect both RS-422 and RS-485 devices simultaneously?
Yes. The two ports operate independently. You can configure one port for a point-to-point RS-422 link and the second port for an RS-485 multipoint network, provided you respect the software configuration constraints for each channel.
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What is the maximum distance for the RS-485 connection?
Standard RS-485 physical layer specifications support distances up to 1200 meters. However, we recommend high-quality twisted-pair shielded cabling to maintain signal integrity at these maximum ranges in electrically noisy environments.
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Does this unit require special firmware for older CENTUM systems?
The ALR121-S50 serves as a standard hardware component. Most CENTUM system software versions recognize this unit automatically; however, always verify your FCS configuration and software revision compatibility in the system engineering manual before commissioning.
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What causes communication errors with this module?
Most errors stem from improper termination resistors on the RS-485 bus or baud rate mismatches. Verify your parity settings and termination jumpers at both ends of the transmission line to ensure stable data flow.
Additional Information
- 100% Genuine Parts: All products are original and authentic, ensuring reliable industrial performance.
- 30-Day Refund Guarantee: Return any in-stock item within 30 days in original, unopened packaging for a full refund (excluding shipping and fees).
- 12-Month Warranty: Covers defects in materials or workmanship; excludes misuse, normal wear, or unauthorized modifications.
- Worldwide Shipping: We ship via USPS, UPS, FedEx, and DHL. Delivery times vary by country and may be subject to customs or import fees.
- Support & Contact: Technical and warranty assistance is available anytime. Contact us here: Contact.
- Purchase Guidance: Check product specifications and compatibility carefully before ordering to ensure proper application.
Tech & Buying Guide
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