Trace Moisture Measurement with Aluminum Oxide Sensor0 pages

Application Note

Gas Production & Distribution

Trace Moisture Measurement with Aluminum
Oxide Sensor in X-STREAM Process Gas Analyzers
With an Aluminum Oxide sensor, the X-STREAM Process Gas
Analyzer family is capable of measuring trace moisture in many
challenging applications. Key features include:
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-100 °C (-148 °F) to -10 °C (14 °F) dew point
In combination with other measurements in one housing
Factory calibrated / no field calibration needed
Cryogenic Gases, Natural Gas (LNG), Utility Power Generators,
Heat Treating

The sensor measures water in the range from -100 °C (-148 °F) to
-10 °C (14 °F) dew point with an accuracy of +/-2 °C. A ppm sensor is
also available with corresponding water concentrations of
0–100 ... 3000 ppm. Each sensor comes with a factory calibration.

Trace Moisture

Measurement range
Measurement accuracy
Repeatability
Response time (t95)
Operating humidity
Sensor operating temperature
Temperature coefficient
Operating pressure
Flow rate

X-STREAM Process Gas Analyzers
The moisture sensor can be combined with any other X-STREAM
Analyzer technology, including: non-dispersive infrared, ultraviolet,
and visible photometry (NDIR/UV/VIS), paramagnetic and
electrochemical oxygen (pO2 / eO2), thermal conductivity (TCD)
sensor and trace oxygen (tO2). If combined with other measurements
in series, the moisture sensor is always first in the series and
completely tubed with stainless steel to avoid any diffusion of
ambient air moisture to the sensor. A calibration exchange program
(annual interval) is available. The sensor can be used in various
background gases such as CO, CO2 and natural gas.

Trace Moisture (tH2O)
-100 to -10 °C dew point (0–100 ... 3000 ppm)
±2 °C dew point
0.5 °C dew point
5 min (dry to wet)
0 to 100 % r.h.
-40 to +60 °C
Temperature compensated across operating temperature range
Depending on sequential measurement system, see analyzer specification (1)
max. 1500 hPa abs / 7 psig
Depending on sequential measurement system, see analyzer specification (1)
0.2 to 1.5 l/min

*NOTE: 1psi = 68.95 hPa
(1) If installed in series to another measurement system, e. g. IR channel

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