Introduction to the Data Log in FactoryTalk View ME.
In this section, we’ll set up a Data Log in FactoryTalk View ME. Whenever you set up a trend chart, usually, you want a data log model to go along with it. When you set up a trend without a data log, your trend data starts all over when you leave the trend display.
Of course, when we attach a datalog to a trend, the datalog model is always logging data in the background. Even when the trend display is not open.
In this case, we are just going to graph a tag called “SpeedReference”. This tag will be in the datalog model. Therefore, FactoryTalk View ME will be logging the data from my SpeedReference tag periodically. We can open the trend at any time to see the current value, and the past history of the values.
Before we begin, just make sure you have a connection to the processor in FactoryTalk Linx Enterprise. To test the data log, we’ll also create a second display called “Trends” (aside from the main display). Be sure to add navigation buttons for the operator to get to and from the trending display.
Create the DataLog Model
Right-click the Data Log models, and create a new Data Log model.
On the “Setup” tab, be sure to enter the number of data points you wish to keep. In this case, we’ll leave it at default. The “Paths” tab allows you to select a different path to store the data log. Again, we’ll leave this at default.
Under “Log Triggers”, we’ll set this up to log periodically, every one second for example. Your plant application may be different.
Most important is the “Tags In Model”. Be sure to select the tag you wish to log. Remember to refresh folders if necessary when you browse for the tags. Be sure to click “Add”, so your tag appears under “Tags in model”!
Finally click “Close”. We’ll save this data log model as “MySpeedReference”.
Set the Data Log in FactoryTalk View ME to run at startup.
Now that you’ve created the data log, we must configure it to run at startup. In FactoryTalk View ME, we will only have one data log model running at a time. This is different from FactoryTalk View SE.
Go into “Startup” at the top of the Explorer tree. The icon for startup is the green flag. Be sure to turn on Data Logging at startup. Also, be sure MySpeedReference is selected as your startup data log model..
Create the Trend
At last, we are ready to create the trend, and associate the data log model to the trend chart. On the Trend display, add a trend object. Make this object as large as possible on your display. Trends are under Objects | Trending | Trend.
Once you add the object, the property screen appears. First, let’s go to the “Connections” tab and add our SpeedReference tag.
On the Y-Axis tab, I’ll choose “Preset” because I want to enter the minimum and maximum values manually.
We’ll leave the X-Axis tab at default for example. Next, let’s go to “Pens”. Choose a color, and enter the Minimum and Maximum values you expect the pen to be.
Don’t forget to associate your data log model!
Press “Apply”, and OK.
Test your work
To test your work, you must “Test Application”, because we have a background service to test. We also need to use navigation, so click “Applicaton” then “Test Application”.
As you can see, we are now tracking data. Test the data log model by navigating to the main screen, and go back to the trending screen.
For more information, visit the FactoryTalk View ME Category Page.
— Ricky Bryce