Vaisala HMP240 User Manual
Page 56
HMP240
User's Guide
M210300en
54
6.3
Calibration of analogue outputs
The analogue outputs have been calibrated at the factory and since they are
very stable, calibration should be performed only when there is reason to
believe that their adjustments have changed.
6.3.1 With serial commands
Disconnect the security lock jumper!
ACAL <cr>
The outputs on channels 1 and 2 are measured and the measured values (mA
or V) entered as calibration coefficients.
Example: both channels have 0...10 V outputs (set with AMODE command);
enter the voltages measured at the analogue outputs:
>ACAL <cr>
Ch1
U1 ( V ) ? 0.123 <cr>
Ch1
U2 ( V ) ? 9.98 <cr>
Ch2
U1 ( V ) ? 0.120 <cr>
Ch2
U2 ( V ) ? 9.98 <cr>
6.3.2 With display / keypad commands
Disconnect the security lock jumper!
•
Connect an ammeter/voltmeter to the output of channel 1, select Cali
in the main menu and Analog outputs in the Cali menu. The follow-
ing is displayed (the quantity can be either mA or V):
•
Enter the measured lower end current/voltage on channel 1:
•
Enter the measured upper end current/voltage on channel 1:
•
Connect the meter to the output of channel 2 and enter the measured
lower end current/voltage on channel 2: