User`s guide

Chapter 4 ______________________________________________________________ Maintenance
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Figure 114 Probe Maintenance
Changing the HUMICAP®180 Humidity Sensor
Unscrew the filter. Remove the damaged sensor and mount a new
HUMICAP®180 humidity sensor in its place. Handle the sensor with
care. Calibrate the probe using a two-point calibration procedure.
Humidity Calibration
For a high-accuracy two-point calibration, use a Vaisala HMK15
calibrator and saturated salt solutions. Refer to the appropriate manual
for details.
Easiest way of doing the calibration is to use HMI41 Indicator with the
HMH40-MAWS Handle for the probe head. Note that this setup is only
for relative humidity and no temperature readings are displayed.
The following numbers refer to Figure 114 on page 153.
1 = Adjustment trimmers: W = wet, D = dry, (T = temperature; for
factory use only)
2 = O-ring for sealing the probe weather tight