Ingersoll-Rand HC-103, User Manual

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INSTRUCTION MANUAL
Sahara Moisture Transmitter
Reference IR-085 Rev 3
Page 12 of 16 01/10/2014
VIII. Helpful Information (continued)
5. Any cross checking between two or more similar instruments should be done
at identical times and conditions. This is even more important when dissimilar
instruments are checked, one against another. It’s not possible to use some
makes of moisture meters under flowing conditions (in situ) on stream or at
line pressures. Some are unstable or are effected by temperature changes or
other variables.
6. Certain contaminants can cause false readings, at best, desensitize the probe.
The system will have to dry out before data can be taken again.
7. Cleanliness is essential. Sampling techniques and set-up procedures should
be standardized. Manufacturer’s specs on sampling and measuring techniques
should be followed to the letter.
8. Spare probes should be bought. This will allow checking one against another
and will avoid having the meter out of service when the probes are in the lab
for recalibration.
9. Everyone involved should be as knowledgeable as possible on the difficulties
of moisture measurement, the use of equipment, and the meaning of data.
10. Define problems carefully. The right approach to equipment selection and
measurement techniques will instill confidence in the end results.
B. Measuring Dew Points: Pressure vs. Atmospheric
1. The SMT will measure either pressure or atmospheric dew points. For many
applications, measuring pressure dew point may be more meaningful.
2. To measure pressure dew points, connect the supply line to the inlet of the
sample cell. Slowly open the inlet valve fully and close the outlet valve. The
sample cell should now be pressurized. Slightly open the outlet valve. The
instrument is now measuring pressure dew point.