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Pyxis ST-774 Ultra-Low Inline Dissolved Oxygen Sensor with Flow Cell

Ultra-low range inline luminescent DO sensor with flow cell (0.1ppb-2,000ppb). Dual 4-20mA + RS-485, 8-pin.

Pyxis Lab
Optical/Luminescent Sensor
Water Treatment Line

Pyxis ST-774 Ultra-Low Inline Dissolved Oxygen Sensor with Flow Cell

Model:
ST-774
Brand:
Pyxis Lab

The Pyxis ST-774 is an ultra-low range inline luminescent dissolved oxygen sensor for trace-level DO monitoring from 0.1ppb to 2,000ppb, avoiding the membrane replacement and electrolyte refills needed by older galvanic and polarographic sensors. It includes a flow cell for stable inline sampling and outputs data via 4-20mA analog and RS-485 Modbus through an 8-pin connector.

Trace-level detection — measures dissolved oxygen down to 0.1ppb, suited to ultra-pure water and boiler feedwater monitoring
Maintenance-free sensing — luminescent optical technology avoids membrane replacement and electrolyte refills
Trace-level detection — measures dissolved oxygen down to 0.1ppb, suited to ultra-pure water and boiler feedwater monitoring

Description

The Pyxis ST-774 is an ultra-low range inline luminescent (optical) dissolved oxygen sensor built for trace-level DO monitoring, covering a range of 0.1ppb to 2,000ppb. As with other Pyxis luminescent DO sensors, it avoids the membrane replacement and electrolyte refills required by older galvanic and polarographic technologies.

The sensor includes a dedicated flow cell that stabilizes sample presentation for accurate inline measurement at trace concentrations. Data is output through both 4-20mA analog and RS-485 Modbus via an 8-pin connector, allowing integration with plant monitoring and control systems.

Its ultra-low detection range makes it particularly suited to applications where trace dissolved oxygen must be tracked with precision, such as high-purity water systems.

Why Use This

Ultra-Low Range Detection

Measures dissolved oxygen from 0.1ppb to 2,000ppb, suited to boiler feedwater and other trace-level applications.

Stable Inline Sampling

The included flow cell provides a controlled sampling environment for consistent inline readings.

Low Maintenance

Luminescent optical sensing removes the need for membrane replacement and electrolyte refills.

Applications

  • Ultra-pure water monitoring — trace-level DO detection down to 0.1ppb
  • Boiler feedwater monitoring — tracking dissolved oxygen at the low concentrations relevant to feedwater quality
  • Inline process water quality monitoring — continuous DO tracking via the integrated flow cell

FAQ

What measurement range does the ST-774 cover?

It measures dissolved oxygen from 0.1ppb to 2,000ppb, an ultra-low range suited to trace-level monitoring.

Why does this sensor include a flow cell?

The flow cell provides stable inline sample presentation, which supports accurate trace-level DO readings.

Does the ST-774 require membrane or electrolyte maintenance like older DO sensors?

No. It uses luminescent optical sensing, which avoids the membrane replacement and electrolyte refills needed by galvanic and polarographic sensors.

How does the sensor connect and output data?

It connects via an 8-pin connector and outputs data through both 4-20mA analog and RS-485 Modbus.

Download

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

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