National Instruments BridgeVIEW Manuel D’Utilisation

Page de 455
Chapter 6
Historical Data Logging and Extraction
© National Instruments Corporation
6-7
You will display previously logged data, which is included in the 
BridgeVIEW\Activity\Data
 directory. It contains a 25-minute run 
of data. You can change the time axis to display the first minute of this 
data. 
3.
Run the VI. The trend displays one minute of data. You can use the 
panning tool to grab the plot and scroll to the left or right to show more 
data. Hold down the <Shift> key while you pan to constrain the 
movement to the horizontal direction.
4.
Stop the VI.
5.
Modify the Block Diagram to incorporate statistics. 
a.
In the block diagram, pop up on the wizard lock and select 
Release Wizard Lock. Now, you can edit the diagram to 
incorporate statistics into your data retrieval application.
b.
Using a For Loop and the 
Historical Trend Statistics.vi
 
(Functions»Historical Data), build the diagram as shown below. 
If you click and drag the Positioning tool inside the case structure 
while holding down the <Ctrl> key, the diagram will expand to 
give you some room to add the new diagram code.