Adjustment Using A Computer - Vaisala CARBOCAP GMW90 Series User Manual

Chapter 5 _______________________________________________________________ Maintenance
VAISALA ________________________________________________________________________ 69

Adjustment Using a Computer

For more detailed instructions on using the Vaisala USB cable and a
terminal application, see section Connecting With a Computer on page
34.
For a description of the serial commands, see section Calibration and
Adjustment Commands on page 53.
1. Connect the GMW90 series transmitter to your computer using the
Vaisala USB cable (order code 219690).
2. Start a terminal application and open a new session to the service
port of the transmitter. The serial line settings are 19200, N, 8, 1.
3. Before changing the adjustment, issue the following commands to
see the transmitter's current adjustment information:
pass 9000
cco2
ct
crh
ctext
cdate
Note that the CRH command is not available if your transmitter
does not support humidity measurement.
4. Place the entire transmitter in the desired reference condition and
allow the measurement to stabilize. Follow the stabilization from
the serial line (output from the R command) or the display.
5. You can now use the CCO2, CT, and CRH commands to adjust
the transmitter's measurement. Refer to the command descriptions
for the available options.
6. After performing the adjustment, verify from the serial line or the
display that the measurement has been corrected.
7. After completing the adjustments, you can enter a descriptive text
string in the transmitter's memory using the CTEXT command,
and note the adjustment date using the CDATE command.