2.2.2 Detecting Hygroscopic Salts
The MMS instrument can be used as a basic salts detector when used with the Moisture
Probe, filter papers and distilled water (not included). Moisten the filter paper with the
water and take a reference reading across it with the Moisture Probe. Then place the
moistened filter paper against the surface of interest and hold in place for 30 seconds.
Remove the paper and place the pins of the Moisture Probe across the paper again
and observe the reading and compare with the original reference reading. If the
difference is more than 20 points there is significant salts contamination that may
warrant further investigation.
3. Hygrometer Mode - Selection and Use
To use the MMS as a hygrometer, connect the Hygrostick probe directly into (EC1) or
indirectly, by means of the Hygrostick extension lead. Turn the MMS on by pressing .
Select the hygrometer mode by pressing successively until the word HYGROMETER
is visible in the top left corner of the LCD. Then press to select relative humidity
(%rh), ambient temperature (T
AIR
) or dew point temperature (T
DEW
) as required.
Temperature values can be displayed in
O
C or
O
F (see section 5 for setup).
%rh and T
AIR
measurements are made by the
Hygrostick sensor and the MMS instrument
uses these values to calculate T
DEW
. When
using the MMS to measure the conditions in
air, the Hygrostick probe is normally
connected directly to the instrument. When it
is impractical or awkward to use the
instrument in this way, the Hygrostick
extension lead may be used to connect the
Hygrostick to the instrument. Typically, the
extension lead will be used when taking
readings from Hygrostick probes that have
been embedded in structures such as walls
and floors.
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