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Application of the Hygrometer (900-901D1)
A-7
June 2003
Aluminum Oxide Probe
Maintenance
Other than periodic calibration checks, little or no routine moisture
probe maintenance is required. However, as discussed in the previous
section, any electrically conductive contaminant trapped on the
aluminum oxide sensor will cause inaccurate moisture measurements.
If such a situation develops, return of the moisture probe to the
factory for analysis and recalibration is recommended. However, in
an emergency, cleaning of the moisture probe in accordance with the
following procedure may be attempted by a qualified technician or
chemist.
IMPORTANT:
Moisture probes must be handled carefully and
cannot be cleaned in any fluid which will attack its
components. The probe’s materials of construction
are Al, Al
2
O
3
, nichrome, gold, stainless steel, glass
and Viton
®
A. Also, the sensor’s aluminum sheet is
very fragile and can be easily bent or distorted. Do
not permit anything to touch it!
The following items will be needed to properly complete the moisture
probe cleaning procedure:
•
approximately 300 ml of reagent grade hexane or toluene
•
approximately 300 ml of distilled (not deionized) water
•
two glass containers to hold above liquids (metal containers should
not be used).
To clean the moisture probe, complete the following steps:
1.
Record the dew point of the ambient air.
2.
Making sure not to touch the sensor, carefully remove the
protective shield from the sensor.
3.
Soak the sensor in the distilled water for ten (10) minutes. Be sure
to avoid contact with the bottom and the walls of the container!
4.
Remove the sensor from the distilled water and soak it in the clean
container of hexane or toluene for ten (10) minutes. Again, avoid
all contact with the bottom and the walls of the container!
5.
Remove the sensor from the hexane or toluene, and place it face
up in a low temperature oven set at 50°C ±2°C (122°F ±4°F) for
24 hours.
Содержание Moisture Image 1 Series
Страница 2: ...Moisture Image Series 1 Service Manual ...
Страница 8: ...Chapter 1 ...
Страница 31: ...Chapter 2 ...
Страница 61: ...Appendix A ...
Страница 94: ...June 2003 A 32 Application of the Hygrometer 900 901D1 Figure A 2 Moisture Content Nomograph for Liquids ...