Pyxis ST-588

An inline sensor designed to measure both PTSA (0–200ppb) and Fluorescent Polymer (0–20ppm)

The ST-588 inline sensor is a proprietary design for the direct measurement of both PTSA (365nm ex/ 410nm em) and “Fluorescent Polymer” (410nm ex / 450nm em) for use in industrial cooling water and process treatment applications. Through significant research and development, Pyxis Lab has developed the ST-588 combination inline sensor to independently measure both PTSA on a present scale of 0-200ppb (500 ppb capable) and Fluorescent Polymer on a scale of 0-20ppm. Customized scales are also available on request.


The ST-588 offers Pyxis proprietary algorithms to determine the concentrations of PTSA and active polymer residual simultaneously while measuring sample turbidity and color in highly contaminated waters (ie. <150 NTU and 10 ppm Fe) for internal compensation. The ST-588 offers a combination of dual (2x) 4-20mA as well as RS-485 Modbus output signals, one for PTSA and one for Fluorescent Polymer.

The ST-588 is provided in CPVC with the standard Pyxis ST-001 inline 3⁄4” FNPT Tee assembly, 5-foot 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-588SS is offered in 304L Stainless Steel with 3⁄4” FNPT ports for high pressure applications.

The ST-588 is Bluetooth enabled for wireless cleanliness diagnostics and calibration when used with MA-CR Bluetooth or PowerPACK Series Bluetooth Adapters and the uPyxis APP for Mobile or Desktop devices.


Product Range:

ST-588: CPVC
Low cost CPCC contacting sensor
ST-588SS: Steel
Toroidal non-contacting PEEK sensor
ST-100: Tee
Low cost CPCC contacting sensor
100 psi
ST-001 tee inc
290 psi
3/4" thread

Typical applications

Built for industrial cooling water and process treatment applications.

Product information

Alternative products

Pyxis: ST-500 Inline Sensor
Pyxis: ST-500



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Sensys Ltd

Head Office
Unit 9 Pond Close
Walkern Road
United Kingdom

01438 759 595

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