Vaisala Calibration of Series HMDW2030 and HMP130 Transmitter with HMI41 - Manual (Page 8)

HMI41 Calibration Option
Operating Manual
19165ZZ-U220en-1.1
4 1996-08-29
offset
gain
test
connector
Figure 2.3 Calibration connector and potentiometers in
the HMD 20/30UB/YB transmitters
gain
offset
test
connector
Figure 2.4 Calibration connector and potentiometers in
the HMW 20/30UB/YB transmitters
2.2 Calibration
After having connected the cable, turn the HMI41 on with the ON/OFF button
and wait until a text similar to the following appears on the display:
RH %
Numbers on the first line indicate the RH measured by the transmitter, and
numbers on the second line indicate the RH measured by the HMI41 reference
probe. If you wish, you can now adjust the transmitter:
•
Wait until the readings have stabilized and adjust the calibration
potentiometers (Figures 2.2 - 2.4) until the readings on the first and
the second line are the same. It is recommended to use the offset
potentiometer if the RH is <65 %RH and the gain potentiometer if the
RH is >65 %RH.