Vaisala Hydromet Data Collection Platform - Manual (Page 61)

Chapter 3 _____________________________________________ Configuring Modules and Sensors
VAISALA_______________________________________________________________________ 59
Scaling of Data
All data values must be properly scaled to fit into the output range of the
Nokeval converter outputs. You can carry out the scaling using two
alternative methods:
- Configuring the QML logger to scale the data. This is performed
using a User definable conversion, configured in the Lizard
Calculations view.
- Configuring the Nokeval converter to scale the data. Refer to the
Nokeval user manual for details (at www.nokeval.com).
Handling of Invalid Data
The QML logger will not send a command if the data value is invalid,
that is, the report includes the character '/'. The Nokeval converter can
be configured to invalidate the output if no command has been received
within a specified time (see the appropriate Nokeval user manual for
details). Therefore, the system can be configured so that an invalid data
value will invalidate the analog output of the converter. In this case, a
separate report should be used to control each analog output, that is, the
OUT CH command should be used, instead of the OUT SCAN
command.
Alternatively, any specific data reading can be sent when the data value
is invalid, by specifying an invalid data indicator for the data cell in the
report.
Timing of Reports
Up to 32 reports can be generated successively at the same
synchronization time. The QML logger will queue the commands and
process them one by one.
If more than 32 reports are needed, the synchronization times of the
report generation events must be adjusted so that no more than 32
commands will overlap each other.