Pyxis ST-500 Inline PTSA Sensor
Real-time inline PTSA sensor for tracking inhibitor dose in cooling and boiler water treatment programmes. Measures PTSA using fluorescence technology across 0–300ppb with automatic colour and turbidity compensation, holding accuracy even in samples with iron contamination or elevated turbidity.
Pyxis ST-500 Inline PTSA Sensor
The ST-500 Inline PTSA Sensor provides continuous, real-time monitoring of inhibitor concentration in fluorescence-traced cooling and boiler water treatment programs, replacing periodic manual sampling. Its flow-through optical design uses multi-wavelength fluorescence measurement to compensate for color and turbidity interference, maintaining accuracy even with iron contamination or elevated turbidity. Beyond PTSA, the ST-500 series also supports fluorescein and NDSA tracers for both cooling tower and boiler applications.
Description
The ST-500 Inline PTSA Sensor gives operations teams continuous, real-time monitoring of inhibitor concentration in fluorescence-traced water treatment programs, replacing periodic manual sampling. It feeds directly into dosing control logic, helping keep treatment concentration within a tight band around setpoint as cycles of concentration or heat load change.
Its flow-through optical design uses multi-wavelength fluorescence measurement to compensate for color and turbidity interference — an area where many competing sensors lose accuracy. The ST-500 maintains performance in samples with up to 100 NTU turbidity and 5ppm iron. Beyond PTSA, the ST-500 series also supports fluorescein and NDSA tracers, extending its use across both boiler water and cooling tower treatment programs.
Built with a CPVC, IP67-rated body and installed via the included ST-001 inline tee (3/4″ FNPT), the sensor outputs isolated 4-20mA analog and RS-485 digital signals for integration with existing control systems. Adding the MA-WB Bluetooth Adapter enables wireless calibration and diagnostics through the uPyxis mobile app.
Why Use This
Continuous, Real-Time Dosing Control
Feeds directly into dosing control logic to keep treatment concentration within a tight band around setpoint, regardless of cycles of concentration or heat load.
Accurate in Difficult Water
Multi-wavelength fluorescence compensates for color and turbidity, maintaining accuracy in samples with up to 100 NTU turbidity and 5ppm iron.
Wireless Calibration and Diagnostics
The optional MA-WB Bluetooth Adapter enables wireless calibration, cleanliness diagnostics, and monitoring through the uPyxis mobile app.
Applications
- Cooling tower treatment programs — continuous PTSA-based inhibitor monitoring for dosing control
- Boiler water treatment — supported via fluorescein and NDSA tracer compatibility
- High-turbidity or iron-contaminated water systems — maintains accuracy up to 100 NTU turbidity and 5ppm iron
- Remote sensor diagnostics — MA-WB Bluetooth Adapter enables wireless calibration via the uPyxis app
FAQ
What tracers can the ST-500 measure?
Beyond PTSA, the ST-500 series extends to fluorescein and naphthenic disulfonic acid (NDSA), covering both boiler water and cooling tower treatment programs.
How accurate is it, and does dirty water affect readings?
The sensor is rated to ±1ppb accuracy and maintains performance in samples with up to 100 NTU turbidity and 5ppm iron, conditions that would distort a standard fluorometer.
How does it install and connect?
It installs via the included ST-001 inline tee with a 3/4″ FNPT connection, and outputs isolated 4-20mA analog and RS-485 digital signals for dosing control integration.
Can I calibrate it without a wired connection?
Yes, with the optional MA-WB Bluetooth Adapter, which enables wireless calibration, cleanliness diagnostics, and monitoring via the uPyxis mobile app.
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