Pyxis ST-540-N Inline Stainless Steel Low Range NDSA Sensor
Stainless steel inline NDSA tracer sensor, low range (0-20ppb). 4-20mA + RS-485, 7-pin.
Pyxis ST-540-N Inline Stainless Steel Low Range NDSA Sensor
The Pyxis ST-540-N is an inline sensor that measures naphthalene disulfonic acid (NDSA) tracer levels, supporting boiler and process water treatment programmes using NDSA-tagged chemistries. It reports concentration across a 0-20ppb range and communicates via 4-20mA analog output and RS-485 Modbus through a 7-pin connector. Its stainless steel body is built for high-pressure process line installations.
Description
The Pyxis ST-540-N is a low-range NDSA (naphthalene disulfonic acid) tracer sensor with a stainless steel body, designed for boiler and process water treatment programmes using NDSA-tagged chemistries where trace-level accuracy matters. Its narrow 0-20ppb range improves resolution at low concentrations, compared to the standard-range ST-540 models.
The stainless steel construction is built for high-pressure process line service, and the sensor communicates via a 4-20mA analog output and RS-485 Modbus, wired through a 7-pin connector for integration with control and monitoring systems.
It is intended for treatment providers who need precise, trace-level verification of NDSA-tagged chemical feed in demanding process water applications.
Why Use This
Continuous tracer monitoring
Measures naphthalene disulfonic acid (NDSA) tracer levels in real time across a 0-20ppb range, giving operators direct visibility into treatment chemical performance.
Easy control system integration
Dual 4-20mA analog and RS-485 Modbus outputs through a 7-pin connector let the sensor feed data straight into existing SCADA or controller setups.
Built for high-pressure lines
The stainless steel housing withstands high-pressure process water service where standard sensor bodies would not be suitable.
Applications
- Trace-level NDSA monitoring — improved resolution across a 0-20ppb range
- High-pressure boiler and process water lines — stainless steel body for demanding service
- NDSA-tagged treatment programs — continuous chemical feed verification
- Control system integration — 4-20mA and RS-485 Modbus outputs for automated monitoring
FAQ
What makes the ST-540-N a low-range sensor?
It measures NDSA tracer across a narrower 0-20ppb range, improving resolution for trace-level concentration tracking compared to standard-range NDSA sensors.
Is it built for high-pressure applications?
Yes, its stainless steel body is built for high-pressure process line service.
What treatment programs does it support?
It supports boiler and process water treatment programmes using NDSA-tagged chemistries.
How does it output readings?
It communicates via 4-20mA analog output and RS-485 Modbus through a 7-pin connector.
Resources
Related Products
Stainless steel ozone + pH sensor, 0-2ppm, sensor only with no flow reservoir. Dual 4-20mA + RS-485, 8-pin connector.
CPVC oxidizer + pH + temperature sensor measuring Ozone 0.00-2.00ppm with pH compensation to pH 9.0. Replaceable front-loading reference electrode, Bluetooth-ready with MA-CR adapter.
Compact dual-channel controller for pH and ORP monitoring with direct pulse output to dosing pumps.
PVDF injection quill with integral non-return valve for safe chemical injection into pressurised pipelines.
Other Models in This Line
Latest Resources
Need help with selection or sizing?
Our engineers are ready to evaluate your requirements and recommend the right solution.