Yokogawa Releases New 2-Wire Transmitter FLXA21®

The Yokogawa FLXA21® is the new generation of two-wire liquid transmitters with a new modular design for continuous on-line measurements in industrial installations. It provides the flexibility for either single or redundant measurement. The FLXA21 modular design offers the flexibly to assemble a variety of systems for applications measuring pH/ORP, Contacting Conductivity (SC), Inductive Conductivity (ISC) or Dissolved Oxygen (DO).

For redundant measurement, the FLXA21 supports up to two sensors of the same type: pH/ORP and pH/ORP, SC and SC, and DO and DO, thereby reducing installation costs and saving panel space. In addition, this configuration provides a highly reliable backup system. By adding an HIM (HART Interface Module) device, the FLXA21 can be programmed for additional functionalities. These include a variety of calculated data from the two measurement inputs. When used as a redundant system, the main output parameter is automatically switched over to the second sensor output in case of the main sensor's failure.

The FLXA21 incorporates the same unique touch screen Human Machine Interface (HMI) and simple intuitive menu structure as the Yokogawa EXAxt450 series. Any of 12 different languages can be selected along with advanced features and functions such as sensor self-diagnosis and maintenance time estimation.

The FLXA21 provides industry proven measurement accuracy by incorporating essential temperature compensation and calibration functionalities, with advanced self-diagnostics and sensor wellness indication. A logbook of events and diagnostic data provide useful information sources for preventive maintenance.

The FLXA21 is housed in a robust NEMA 4X, IP66 mountable enclosure which meets all the CE regulatory standards. It is designed with the option to select enclosure housings to meet specific industry needs. Plastic, stainless steel or stainless steel with corrosion resistant coating is available.

FLXA21 Features

Low Long Term Cost of Ownership

  • Simple HMI touch screen menu structure
  • Enclosure choices: plastic stainless steel, or stainless steel + coating

Reduced Cost to Install System

  • 4 basic parameters available: pH/ORP, SC, ISC, and DO
  • Simple start-up via, Quick setup menu
  • Adaptable for either Redundant or Dual measurements


  • Redundant sensor configuration
  • Diagnostics including sensor wellness indication   

About Yokogawa Corporation of America

Yokogawa Corporation of America is the North American division of Yokogawa Electric Corporation and a key part of Yokogawa's global network of 25 manufacturing facilities and 80 companies spanning 54 countries. Since its founding in 1915, the US $3 billion company has been engaged in cutting-edge research and innovation, securing more than 7,200 patents and registrations, including the world's first digital sensors for flow and pressure measurement. Industrial automation and control, test and measurement, information systems and industry support are the core businesses of Yokogawa. For more information about Yokogawa, please visit our website www.yokogawa.com/us.

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