Vaisala HMT360Series - Automatic Two-Point RH Calibration

Calibration and adjustment ____________________________________________________________
Vaisala _________________________________________________________________________ 48
Relative humidity calibration
Automatic two-point calibration
(only with HMT360 with display)
The automatic calibration procedure is a user friendly way to calibrate
with salt solutions; user do not have to feed the reference values to the
HMT360. The transmitter displays the accurate value based on the
measured temperature and the Greenspan table stored into the
transmitter memory. The display chart of the calibration procedure is
presented in FIGURE 9-3 Display chart of the automatic calibration
procedure.
− Set the calibration dip switch to ENABLED position and select RH
calibration by using switches 3 and 4 (see Chapter 5: Dip switch
functions).
− Remove the filter and insert the probe head into a measurement
hole of the LiCl salt chamber in the humidity calibrator.
Acknowledge by pressing the button E. Alternatively select the 0.1
(humidity in Nitrogen) with buttons ▲ and ▼. Acknowledge with
the button E.
− The transmitter remains to wait for the process stabilization (10-15
min) and then stores the correction.
− Insert the probe head into a measurement hole of the NaCl salt
chamber in the humidity calibrator. Acknowledge by pressing the
button E. Alternatively you can select K2SO4 value with buttons
▲ and ▼.
− The transmitter remains to wait for the stabilization and then stores
the correction. The text CAL PASS is displayed after the calibration
is performed.
NOTE
Remember to restore the dip switch settings.