Vaisala HM70 - Manual (Page 49)

Chapter 9 ______________________________________ Calibration and Adjustment of Transmitters
VAISALA _______________________________________________________________________ 47
The first row shows the reading of the probe/transmitter
connected to the port I, the second row shows the reading of the
probe/transmitter connected to the port II. The third row RH/T is
the difference between the readings of the ports. By pressing
BACK you return to the selection display.
Figure 8 Example of the RH display
Field Checking and Adjustment of
Humidity by Using a Calibrated
Reference Probe
Follow the steps from 1 to 12 and continue as follows:
13. Ensure that the probes are located in the same conditions.
14. Wait until the readings have stabilized. If the difference between
the humidity readings is less than 2 % RH, there is no immediate
need for adjustment.
15. Adjust the transmitter reading to correspond a reading of the
reference probe by pressing ADJUST .
16. Select To same as RH
I/II
. Press SELECT.
17. Confirm by pressing YES
18. Press BACK, EXIT, EXIT to return to the basic display.
1-Point Humidity Adjustment by
Using a Calibrator
You can use Vaisala humidity calibrator HMK15 to achieve the
reference humidities. MI70 indicator is working as a communicator in
the calibration procedure.
Follow the steps from 1 to 12 and continue as follows:
13. Insert the transmitter probe to the reference humidity