Kipp&Zonen Brewer MkIII - Manual (Page 24)

MKIII SERVICE MANUAL 19
4.16 BREATHER DESICCANT CARTRIDGE
The breather desiccant cartridge allows the Brewer to compensate for normal pressure changes,
while preventing the influx of moist air. Note that the breather desiccant does not remove moisture
from the Brewer. Extra desiccant is needed to remove moisture from inside the instrument.
Breather desiccant is housed in a plastic container with a breathing tube placed at the bottom of
the cartridge. The other end of the tube is connected to a port at the bottom on the underside of the
Brewer and is exposed to the outside air. As the air is drawn in from the outside, the air is dried as
it passes the desiccant. Reference figure 10.8.
4.17 HUMIDITY SENSOR (OPTIONAL)
The humidity sensor is a monolithic IC sensor that provides a voltage output proportional to relative
humidity. The sensor is buffered by an Op Amp and the output is connected to one of the analog
input channels of the A/D converter. A temperature sensor is located near the humidity sensor to
provide temperature compensation for the device. The two measured values, relative humidity and
temperature allow the absolute moisture to be calculated. The absolute humidity (grams/m
3 ) value
is displayed on the PC screen along with a numerical “moisture index” value. Refer to Figure 10.4-5
for the sensor specifications and Figure 10.4-6 schematic for the humidity sensor assembly.
4 OPERATING TEST FAILURES