Navigation:  Tutorials > Basic tutorials > DEWESoft 7.0  data acquisition, processing, analyzing and storage software Post processing

A great new feature of DEWESoft version 7 is post processing. All the mathematic which are available during Acquisition (measurements) can now be added on also to already stored data files.

Let's acquire some analog data with the microphone and open the file.

 

Now press the "Offline math" button . This will open the "Setup" tab sheet in Math section. Here you are able to add any math just like being in Acquisition (measure) mode.

 

After going back to Review, the Offline math button changes to Recalculate. Let's add new recorder by pressing a plus button. When adding AI3/Filter channel which we have just created, we can see ... nothing. Recorder is empty. The reason for that is because we need to issue the Recalculation manually. The big benefit f that is that we can define a region where the data is recalculated.

 

Imagine you have a huge file. Add a filter to many channels, issue the recalculation, go for a coffee, come back and see that it would be much better to choose different filter type.

DEWESoft offers you to zoom in the region and calculate only for that region. After pressing Recalculate button, filter is calculated and the button turns back to Offline math. If the result is not perfect, we can go back to Setup (either by clicking Setup tab or clicking on Offline math) and change the math.

 

Let's change the cutoff frequency from 100 Hz to 2 kHz (in the Setup screen of IIR filter). After doing this, we can see that the status of the math channel changed from Calculated to Offline and the online values says "Waiting calculation".

 

Go back to review and press Recalculate. New calculation will be performed and will replace previous one. When we are satisfied with the result on one section of the file, we can zoom out to the whole recording. We will see only a part of the calculated channel and the rest will be empty. The Offline math changes again to Recalculate. After pressing Recalculate we can go for a coffee with a good feeling that everything will be correct when we it will be recalculated.

 

We can add all kind of math channels, not only formulas, filters and statistics, but also power, order tracking, torsional vibrations, combustion, basically everything what is possible online.

Let's look at another nice usage of offline math.

Go back to math setup and add another math block - this time Basic statistic. Go to the setup and select Single value minimum and maximum.

 

We have now two more channels: AI3/MIN and AI3/MAX.

Go back to Review and add those channels on the recorder. For practicing display settings we can also add some meters. When zooming in and pressing Recalculate we get the min and max values for that zoomed region.

 

Another very nice option is the Auto recalc . Instead of pressing Recalculate every time a new section is chosen, Auto Recalc will do that automatically.

The last step is then saving these channels to the data file. When we have zoomed out in full and Recalculated the channels, we can press Save button to store math settings, visual controls as well as calculated channels.