Using Calibration Data Exchange Files (CDF)

V8.7 allows to add CDF files CDF stands for Calibration Data Format (ASAM standard). It stores calibration parameters of different data types, the physical values and unit. CDF files is an XML-based format, which can be easily validated, edited, imported and exported by calibration tools and XML editors. to a configuration.

You can perform the following actions:

To add a CDF file
To use CDF files for the Lookup Table functions
To use a VALUE from an CDF file as constant

To add a CDF file

CDF files can be handled in the same manner as measure files. To see how you can add, replace, or delete them, see Adding, Replacing, and Removing Measure Files. Parameters (i.e. curves or maps) provided via a CDF file are listed in the Variable Explorer.

Note
Axis values of curves and maps used as input for Lookup Tables must have monotonous axis points. If V8.7 founds an inconsistency, an error or warning icon appears.

If CDF files have been deleted earlier and the configuration thus contains calculated signals with missing input signals, a dialogue opens that allows you to either add or replace the selected CDF files. For more information, see To replace a measure file.

To use CDF files for the Lookup Table functions

Curves and maps from CDF files can be used as input signals for the functions Lookup table (curve) and Lookup table (map) in the Calculated Signals window.

The needed inputs for these functions are:

the curve or map
a measured signal
the interpolation mode (constant or linear)

To use a VALUE from an CDF file as constant

A scalar parameter 'VALUE' from a CDF file can be used in MDA as a constant. This allows to display in an oscilloscope a horizontal line throughout the whole time range.
In a table instrument an entry for the constant VALUE is shown at the very first time stamp of a measurement files assigned to the configuration.
A scalar value can also be used a constant in a calculated signal. Optionally a fixed time raster must be assigned, if no other signal is used in the formula.

To update or modify the values of the curves and maps, use an external editor. Afterwards, you can replace the CDF file by using the replacement function in the File Explorer. For more information on how to replace a file, see To use the "Add or Replace Files" dialog.

To see how you can replace a measure file, watch our video Replacing Measure Files.