Vaisala HMT130 - Manual (Page 62)

User's Guide _______________________________________________________________________
60 ___________________________________________________________________ M211280EN-B
NOTE If you do not wish to perform the two-point RH adjustment at this time,
press the ADJ button one more time. The green indicator LED turns off
and the red indicator LED begins to blink slowly (800ms cycle time) to
indicate T calibration state. Now you can continue following the
instructions from step 7 onwards.
If one-point calibration is done at more than 50% RH, a gain adjustment
is done instead of an offset adjustment.
6. Insert the probe into the high end reference chamber (for example,
NaCl: 75 % RH chamber in the humidity calibrator HMK15) and
do the high humidity gain adjustment by using the - and + buttons
to make sure the U
out
voltage is correct (you have to press either -
or + at least once even if the value is correct). To finish the RH
calibration, press the ADJ button. The green LED is now turned off
and the red indicator LED begins to blink slowly (800ms cycle
time).
7. HMT130 transmitter is now in T calibration state. Analog output
and optional display will still follow the actual measured T value.
NOTE If you do not wish to perform the T adjustment at this time, press ADJ
button one more time. The red indicator LED is turned off and the
transmitter returns to normal mode. The calibration procedure is now
finished.
8. Insert the probe into a known reference temperature (if Vaisala
Humidity Calibrator HMK15 is not used) and let the temperature
reading stabilize.
NOTE Do not touch the adjustment buttons before the conditions have
stabilized.
9. Using the - and + buttons, make the temperature offset adjustment
by making sure the U
out
voltage is correct (you have to press either
- or + at least once even if the value is correct) and press the ADJ
button. The red indicator LED begins to blink faster (400ms cycle
time).
NOTE If you do not wish to perform the two-point T adjustment at this time,
press the ADJ button one more time. The red indicator LED is turned
off and the transmitter returns to normal mode. The calibration
procedure is now finished.
10. Insert the probe into another reference temperature.