Vaisala HMP230 - Manual (Page 69)

HMP230 SERIES
M210225en-B User's Guide
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• Check that the reading corresponds with the reading of the reference
instrument. If not, adjust the second point.
• If necessary, change the second point reading with the arrow keys and
press ENT.
7.2.2.3. 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 lower reference.
• Connect an ammeter/voltmeter to the analogue outputs (connector
X2). Give command ¡¡l¡. 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.
• 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.
• Change the temperature and check the transmitter against the higher
reference.
• Check that the reading corresponds with the reading of the reference
instrument. If not, adjust the second point.
7.3. Calibration of the analogue outputs
The analogue outputs have been calibrated at the factory and since they are
very stable, calibration of the outputs should be performed only when there is
reason to believe that their adjustments have changed.
7.3.1. With serial commands
Disconnect the security lock jumper!
ACAL
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: