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.
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