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Pyxis ST-540-A Inline NDSA Sensor

Inline NDSA tracer sensor (0-500ppb). 4-20mA + RS-485, 7-pin.

Pyxis
Inline Tracer Sensor
Boiler Water Treatment

Pyxis ST-540-A Inline NDSA Sensor

Model:
ST-540-A
Brand:
Pyxis

The Pyxis ST-540-A 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 0-500ppb range and communicates via 4-20mA analog output and RS-485 Modbus through a 7-pin connector.

Real-time tracer monitoring — 4-20mA analog and RS-485 Modbus outputs feed data directly into control systems
Precise range coverage — calibrated to 0-500ppb for accurate tracking of treatment chemical levels
Real-time tracer monitoring — 4-20mA analog and RS-485 Modbus outputs feed data directly into control systems

Description

The Pyxis ST-540-A is an inline sensor that tracks naphthalene disulfonic acid (NDSA) tracer levels, supporting boiler and process water treatment programmes that use NDSA-tagged chemistries. Continuous inline measurement gives operators real-time confirmation that NDSA-tagged treatment chemical feed is dosing correctly, rather than relying on grab samples.

It reports concentration across a 0-500ppb range and communicates through a 4-20mA analog output and RS-485 Modbus digital signal, both wired through a 7-pin connector for integration with plant control and monitoring systems.

This sensor is intended for treatment providers and plant operators running NDSA-tagged boiler or process water treatment programs who need continuous, automated feed verification.

Why Use This

Continuous tracer monitoring

Measures naphthalene disulfonic acid (NDSA) tracer levels in real time across a 0-500ppb 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.

Applications

  • Boiler water treatment programs — tracks NDSA-tagged treatment chemistries
  • Process water treatment monitoring — continuous inline verification of chemical feed
  • Treatment chemical feed control — real-time data for dosing adjustment
  • Control system integration — 4-20mA and RS-485 Modbus outputs for PLC/SCADA

FAQ

What does the ST-540-A measure?

It measures naphthalene disulfonic acid (NDSA) tracer concentration used in boiler and process water treatment programmes with NDSA-tagged chemistries.

What is its measurement range?

It reports NDSA tracer levels across a 0-500ppb range.

How is it installed?

It is an inline sensor that mounts directly into the process water line for continuous monitoring.

How does it connect to a control system?

It communicates via 4-20mA analog output and RS-485 Modbus through a 7-pin connector.

Download

D25 Product Datasheet
PDF · 1.2 MB
Installation Manual
PDF · 0.8 MB

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