Vaisala PWD22 User Manual page 83

Chapter 5__________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 81
2 mA, PWD22 calculates the current range of 0 ... 1 mA. Otherwise, it
calculates the current range of 0 ... 20 mA.
The analog output calibration procedure is the following:
1. Connect a multimeter between the pink and the blue wires in
PWD22.
2. Give the ACAL command to PWD22.
3. PWD22 sets two-bit values to the DAC hardware and asks for
the corresponding currents. The currents can be measured with a
standard (calibrated) multimeter.
4. PWD22 calculates the bits/current scales.
Following is an example of the calibration (current sink, 20 mA
jumper):
Type the following command:
>ACAL
The output will be as follows:
MEASURED CURRENT (mA)
Then the user enter the value, for example, 21.69.
The output will be as follows:
MEASURED CURRENT (mA) 4.35
The output is the following:
DAC MODE: EXT1
MAX VIS 20000, 20 mA
MIN VIS 180, 4.5 mA
20mA SCALE_1 184.5, SC_0 -2.8
1mA SCALE_1 184.8, SC_0 -1.4
The parameters of the ACAL command in the current range of
0 ... 1 mA are the following:
DAC scale 1
DAC scale 0