Vaisala HMP240 User Manual
Page 55
HMP240 series
M210300en
User's Guide
53
6.2.2.2
With display / keypad commands
•
Leave the reference instrument and the transmitter for at
least 4 hours in the same space so that their temperatures
have time to equalize. Remove the filter cap prior to
calibration.
Disconnect the security lock jumper!
•
Check the transmitter against the reference.
•
Select Cali in the main menu and then T (Ta for the
additional T sensor head); select two-point calibration T
(or Ta) 2 point cal. Change the first point reading with the
arrow keys and press ENT.
•
Change the temperature and check the transmitter again
against the reference.
•
Check that the reading corresponds to the reading of the
reference instrument. If not, adjust the second point.
•
If necessary, change the second point reading with the ar-
row keys and press ENT.
6.2.2.3
With LED commands
•
Leave the reference instrument and the transmitter for at
least 4 hours in the same space so that their temperatures
have time to equalize. Remove the filter cap prior to
calibration.
Disconnect the security lock jumper!
•
Check the transmitter against the reference.
•
Connect an ammeter/voltmeter to the analogue outputs
(connector X2). Give command ¡¡l¡ (or ¡l¡¡ for
the T sensor head). At the first calibration point the LED
on the left flashes; adjust the first point (offset) with the
arrow switches to the same reading with the reference and
press ENT switch.
•
Change the temperature and check the transmitter again
against the reference.
•
Check that the reading corresponds to the reading of the
reference instrument. If not, adjust the second point.
•
If necessary, adjust with the arrow switches to the correct
value and press ENT. At the second calibration point the
second LED from the left flashes.