Question:
The Historic is recording data before communication with the PLC has been established. Can this be avoided?
Solution:
There are two work modes for the Historic: automatic and manual. This is established by the recording time:
If its value is 0, it will work in manual mode: new data will only be recorded when the Historic’s WriteRecord() method is executed.
For any value other than 0, the Historic will work in automatic mode, and will record new data every x seconds, depending on the value chosen by the user. This value can be changed at run time via Historic’s ScanTime property.
To fix the situation above, the Historic can be initially set up to work on manual mode, and then a script can be written to change this property to a different value. Example:
Application.GetObject(“Hist1”).ScanTime = 1000
Another easier possibility is to create a digital link:
To better understand how a digital link works, just download the attached demo application. In it, you will see a switch called Automatic/Manual, which changes the value of the internal tag used in this link.
NOTE: The attached demo application was developed in Elipse v3.2 b238
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