Ametek 303B, User Manual

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3-6 | 303B Moisture Analyzer Manual
Sample System Hook-Up
1. Do the leak test given in Section 4-6.
If the instrument is used to measure moisture in toxic or flammable gases, the GAS
OUT must exhaust to an area deemed safe and appropriate by the local authority having
ju-risdiction.
To prevent damage to the moisture cell, it is necessary to purge your sample line prior
to connecting the analyzer. Failure to do so may void the warranty.
2. Connect a source of gas at 70 to 700 kPa (10 to 100 psi) gauge with a
moisture content of less than 100 ppm to the GAS IN fitting. Nitrogen,
instrument air, argon, or helium is commonly used.
3. Close the BYPASS ADJUST valve. Do not over tighten.
4. Connect a precision flow meter such as the bubble-o-meter (figure 3-4)
to the GAS OUT fitting. The 303B flow meters must be calibrated for all
sample gases (refer to Appendix E for correction factors).
5. Set the SAMPLE ADJUST so that the external flow meter indicates 100
mL/min at 25°C (77°F) and 1 atmosphere.
6. Note the reading on the 303B internal flow meter. You may want to mark
the tube with a permanent marker.
7. Select the lowest ANALOG RANGE that does not cause the recorder to
read full scale.
8. Continue to operate until the displayed moisture level stabilizes.
9. If operating on dc (internal battery), unplug the ac power at the source.
The AC POWER LED should go out and the display reading may fluctu-
ate slightly. This slight difference between ac and dc operation is normal
and will disappear over a short period of time.
10. If the monitor is operating correctly, shut off sample gas and press the
POWER switch (LED off). If it is not operating correctly, review these
procedures to ensure they have been properly followed, and read the
following manual sections. There are troubleshooting procedures in
Section 4.
11. Install the cover and tighten the screws.
!
WARNING
!
WARNING