Yokogawa ALR121-S51 S1 Serial Communication Module

GENERAL

The ALR121 Serial Communication Modules used with a safety control station (SCS) for performing Modbus communication. 

By using the SCS’s Modbus slave communication function, the data in SCS can be set or referred to by the Modbus master which is as separate system from SCS via a serial communication module. Furthermore, the subsystem data such as from sequencers can be set or referred to via a serial communication module using SCS’s subsystem communication function.

These serial communication modules can be mounted on SSC60-, SSC50-, SSC57-, and SSC10- safety control units and SNB10D safety node unit that are connected with safety control units by ESB bus.

Figure A sample configuration of the serial communication modules

HARDWARE SPECIFICATIONS

EXTERNAL DIMENSIONS

Nominal Tolerances:

When the reference dimension is over 0.5 mm and equal or less than 120 mm, its nominal tolerance is ± 0.8 mm, while its combination of nominal tolerance is ± 1.5 mm. When the reference dimension is over 120 mm, its nominal tolerance is in accordance with JEM 1459.

MODEL AND SUFFIX CODES

FAQ for Yokogawa ALR121-S51 S1

Q1: How does the Yokogawa ALR121-S51 S1 optimize high-reliability serial communication in industrial automation networks?
A: The Yokogawa ALR121-S51 S1 is equipped with dual RS-422/RS-485 communication ports and supports half-duplex transmission, enabling dependable data exchange between controllers, field devices, and supervisory systems. Its configurable communication parameters ensure seamless integration with diverse industrial protocols.

Q2: Why is the Yokogawa ALR121-S51 S1 an ideal choice for demanding process control applications?
A: The Yokogawa ALR121-S51 S1 delivers stable communication through support for transmission rates ranging from 1200 to 38400 bps, binary data encoding, selectable parity options, and low transmission latency, making it well-suited for continuous process automation environments.

Q3: What communication flexibility distinguishes the Yokogawa ALR121-S51 S1 from conventional serial interface modules?
A: The Yokogawa ALR121-S51 S1 offers configurable synchronization methods, stop bits, parity settings, and multiple baud rates. Its compatibility with Modbus slave communication and subsystem communication allows it to interface efficiently with both legacy and modern automation architectures.

Q4: Which environmental features enhance the long-term operational reliability of the Yokogawa ALR121-S51 S1?
A: The Yokogawa ALR121-S51 S1 incorporates ISA Standard G3 conformal protection, providing enhanced resistance to corrosive industrial atmospheres. This protective design contributes to improved durability and dependable performance in harsh operating conditions.

Q5: What technical characteristics make the Yokogawa ALR121-S51 S1 suitable for mission-critical industrial communication systems?
A: The Yokogawa ALR121-S51 S1 combines 2-port RS-422/RS-485 connectivity, 8-bit character transmission, configurable parity checking, 1 ms transmission lag, and robust communication stability. These features enable accurate, deterministic, and efficient serial communication in critical industrial control systems.

Recommended

About us

Amikon sells automation equipment around the world. 

With a strong focus on older, obsolete, Automation parts, we pride ourselves in providing high quality parts and services to our customers. 

Our goal is to provide a seamless purchasing experience that trumps the competition. 

Low lead time, with quick shipping and processing is our utmost concern.

Reducing downtime is extremely important to us and our customers take notice! 

All orders are prepared by our expertly-skilled team and thoroughly vetted before each shipment.

Contact: Miya zheng  Email:sales@amikon.cn  Phone/WhatsApp:86-18020776792