Inline & Submersible Sensors
PTSA and Fluorescein Polymer Sensors for Industrial Boiler & Process Water Applications
The ST-500 Series offers a proprietary design that utilises LED light sources for the direct measurement of fluorescein (fluorescein sodium salt/ uranine. This simple, smart sensor is perfect for a water treatment professional working in industrial boiler water and process treatment applications. offers proprietary Pyxis Lab® algorithms to determine the concentrations of fluorescein at levels as high as 600 ppb. Thanks to the state-of-the-art fluorescence technology adopted, the ST-500 series are very forgiving to real world sample water conditions. With its flow-through optical design and multiple wavelength colour/ turbidity compensation algorithm, the ST-500 series probes keep their high performance for water samples with up to 100 NTU turbidity and/ or 5 ppm iron. The sensors offer 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 MA-WB or PowerPACK Series Bluetooth Adapters and the uPyxis APP for Mobile or Desktop devices. The ST-500 Series 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.
Disinfection Sensors. Chlorine or Chlorine Dioxide
The ST-600 Series is uniquely designed to measure the real-time mass/ mass concentration of % chlorine dioxide or bleach (sodium hypochlorite) % chlorine (Cl2). The sensors measure the optical density of the solution using a UV light source. In addition to the main light source and detector, the sensor has a built-in reference light source and detector. Beach can be measured in two ranges; 0-16% & 0-2%. Chlorine dioxide 0-0.35%. Connect it to any device that accepts an isolated or non-isolated 4–20mA input or RS-485 Modbus. As with all Pyxis inline sensors, the sensor can be wirelessly accessed via Bluetooth® when used with the MA-WB Bluetooth Adapter or PowerPACK Series Auxiliary Box and the uPyxis® Mobile or Desktop App.
Optical Luminescent Dissolved Oxygen Sensors
The ST-772 optical luminescent sensor is based on then principle of fluorescence quenching. Stainless steel or CPVC versions.
- 0.004–20mg/L measurement range
- No membrane/ electrolyte replacement
- Simple DO cartridge replacement every 2 years
- Built-In temp & pressure sensor with automatic compensation
- Accurate and stable measurement - ultra-low drift requiring no calibration for up to 2 years
- Built-in transmitter without preamplifier/ meter head
- Dual outputs: 4–20mA isolated signal & RS-485 Modbus
- Slope calibration with air or air saturated water/ zero calibrate with 5% SO3 solution or nitrogen gas
- Submersible or inline tee
The ST-774 is an ultra-low range dissolved oxygen (DO) sensor with a lower limit of detection 0.4 ppb (µg/L). Using fluorescence quenching to determine the partial pressure of dissolved oxygen in water the ST-774 offers the robustness associated with optical DO sensor technology while achieving the ultra-low detection limit compatible to an amperometric DO sensor. The embedded process control board within the ST-774 uses the latest USGS equations to convert the built-in partial pressure and temperature measured to a DO value in ppb (or µg/L).
Corrosion Sensors
The CR-301 is a high pressure/ temperature LPR corrosion rate sensor built for extreme applications. Measure for general (0.001–995MPY) and localised corrosion rate (0.001–100 Index) based on system metallurgy. There is a common industrial misnomer that the use of inline LPR corrosion sensors should be identical to corrosion coupons. The LPR corrosion level represents the real-time electrochemical measurement of corrosion. Measurements gathered from the CR-301 are instant & represent “real-time conditioning” on an MPY scale based on the metallurgy being assessed. The sensor utilises the linear polarisation resistance (LPR) method to produce a raw signal. The corrosion sensor also measures sample water conductivity directly and compensates for the conductivity impact on the LPR measurement. These unique product characteristics make the Pyxis LPR superior in performance and accuracy. In addition the sensor also measures electrochemical noise. The measured noise data is used to calculate an index to quantify the localised corrosion rate also referred to as pitting.
The CR-200 wireless (on right) and CR300 wired corrosion rate sensors are ideal for cooling and process water treatment monitoring where robustness and affordability are a must. The sensor utilises the linear polarisation resistance (LPR) method to produce a raw signal. The raw signal is conditioned, amplified and digitised directly in the sensor itself. This avoids the interferences and attenuation of the raw signal caused by long distance wiring needed for other corrosion sensors. Pyxis corrosion sensors measure sample water conductivity directly and compensate for the conductivity impact on LPR measurement. These unique product characteristics make the LPR superior in performance and accuracy. The sensors also measure for electrochemical noise. The measured noise data is used to calculate an index to quantify the localised corrosion rate also referred to as pitting. Ultra-low corrosion rate measured down to 0.001MPY.
Turbidity Sensors
The ST-730 and 731 ranges are inline turbidimeter sensors designed for a wide range of turbidity monitoring in various applications. Each device is configured with a specific scale for NTU detection, from 0-10, 0-100 and 1-1000 NTU. These sensors are more robust and tolerant to fouling, rendering alternative turbidity sensors inferior due to particulate and air bubble challenges. The sensors give the desired resolution and accuracy in high turbidity applications commonly using suspended solid meters.
- InfraRed LED light source with 90º scattering
- Accurate readings in complex flow systems
- Compact design with a small footprint
- Integrated 4–20mA + RS-485 Modbus outputs
- Bluetooth® enabled
- Wireless diagnostics & calibration
The LT-736 to 739 range of ultra-low (0.001 NTU) turbidity sensors use warm white LED light or InfraRed LED sources. EPA-180.1 compliant. These sensors have a unique flat surface distal end in a quartz glass plate, allowing for extending cleanliness and easy maintenance & prevention of air bubble interference. Available in different maximum scales; 5.000, 40.00 and 1,000 NTU. Sensors are powered by a 24VDC/2W power supply and offer both 4–20mA & RS-485 Modbus output signals. When clean, the unique Pyxis Lab® sensor design offers a calibration stability of <0.02 NTU for up to 1-year of operation with no need for calibration.
