Vaisala DMT346 - Manual (Page 153)

Chapter 7 ___________________________________________________ Calibration and Adjustment
VAISALA _______________________________________________________________________ 153
7. Press YES to confirm the adjustment. Press OK to return to the
adjustment menu.
8. Before closing the adjustment mode, feed the adjustment
information into the device, see section Adjustment Information on
page 151. Press EXIT to close the adjustment mode and return to
the basic display.
Using Serial Line
NOTE Reference humidities must be ~0 %RH and 30 ... 75 %RH. A suitable
product for the two point RH calibration is for example the Vaisala
Humidity Calibrator HMK15.
1. Connect the DMT345/346 to a PC. See section Serial Line
Communication on page 76. Open a terminal program.
2. Carry out the chemical purge.
3. Press the ADJ button.
4. Remove the filter from the probe and insert the probe in the dry end
reference conditions (~0 %RH).
5. Issue the FCRH command and press Enter.
FCRH
6. Wait at least 30 minutes for the sensor to stabilize.
7. Press Enter a few times to check if the reading is stabilized.
8. When the reading is stabilized, give the reference humidity after
the question mark and press Enter.
>fcrh
RH : 11.25 Ref1 ?
RH : 11.25 Ref1 ?
RH : 11.25 Ref1 ?
RH : 11.24 Ref1 ?
RH : 11.24 Ref1 ? 11.3
Press any key when ready ...
9. Now the device is waiting for the wet end reference. Insert the
probe in the wet end reference condition (30 ... 75 %RH). Press any
key when ready.
10. Let the probe stabilize for about 30 minutes. You can follow the
stabilization by pressing Enter.