Pyxis PTSA & polymer sensors

Pyxis ST-500

Pyxis range of PTSA, polymer and flourescent inline sensors, for cooling, boiler & process water applications

The range of PTSA and Polymer sensors comprises:

  • ST-500 - PTSA
  • ST-525 - Fluorescein
  • ST-588 - PTSA & flourescent polymer
  • ST-590 - Flourescent polymer


The ST-500 Series offer Pyxis Lab® proprietary algorithms to determine the concentrations of PTSA while measuring sample turbidity and color in highly contaminated waters (ie. ≤150NTU and 10ppm Fe) for internal compensation. The ST-500 Series offers a combination of 4–20mA as well as RS-485 Modbus output signals and is Bluetooth® enabled for wireless cleanliness diagnostics and calibration when used with the MA-WB or PowerPACK Series of Bluetooth® Adapters and the uPyxis® mobile and desktop app.

The ST-500 Series is provided in CPVC with the standard Pyxis Lab® ST-001 inline 3/4in FNPT Tee Assembly, 5ft Bulk-Head Cable with Quick Adapter and 1.5ft Flying Lead Cable with Quick Adapter, enabling rapid wiring to any microprocessor controller, PLC or DCS system. The ST-500SS is offered in 304L Stainless Steel with 3/4in FNPT ports for high pressure applications.



Typical applications

For use in industrial cooling water and process treatment applications.

Product Range:

ST-500: CPVC
Low cost CPCC contacting sensor
Toroidal non-contacting CVPC sensor
ST-500 SS: Steel
Toroidal non-contacting PEEK sensor
ST-100: Tee
Low cost CPCC contacting sensor
ST-100: Tee
Low cost CPCC contacting sensor
ItemOutputMax rangeAccuracyInstallation
0-200 ppb
0-300 ppb
+/- 1 ppb
ST-001 tee inc
0-40 ppb
0-40 ppb
+/- 0.2 ppb
ST-001 tee inc
ST-500 SS
0-200 ppb
0-300 ppb
+/- 1 ppb
3/4" thread

Product information

Alternative PTSA sensors

Pyxis: ST-588 Inline Sensor



Custom build solutions

Redefine simplicity and flexibility in cooling tower solutions with our plug-and-play service that delivers rapid installation.

We offer standard layout that serves as a solid foundation but we can be customise to meet the unique needs of any client site. We tailor the build to achieve optimal performance.

Our custom builds are popular as a comprehensive solution that's wired and seamlessly integrated meeting any site requirements. Email us today to learn more about our bespoke custom built solutions to speed up your installation and reduce operation or project downtime.


We specialise in delivering tailored product training to empower your team and enhance operational efficiency. Whether you prefer on-site sessions, at your company's location or the convenience of video conferencing, we've got you covered.

Our focus revolves around installation best practices, ensuring seamless product connectivity, and optimising maintenance procedures. Take the first step towards maximising your team's potential. Email us today to learn more about our bespoke training offerings, check availability, and embark on a journey to enhance your team's expertise.

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Sensys Ltd

Head Office
Unit 9 Pond Close
Walkern Road
United Kingdom

01438 759 595

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