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LESSON LIST
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3:23Tag Group Overview
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3:41Driven Tag Group
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2:06Leased Tag Group
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Description
A Leased Tag Group is a Tag Group where Tags vary in execution rate based on whether they are currently being viewed.
Video recorded using: Ignition 8.1
Transcript
(open in window)[00:00] Ignition offers a built in way of executing at one rate, when a tag is being viewed in a client session or designer, and another rate when it's not. Now this is useful when trying to minimize the use of network or PLC resources by only subscribing at the faster rate, when tags are in demand. We can do this by using a leased tag group. So let's start by configuring a new tag group. We'll go into our tag browser and click on the edit tag groups button. I'll add a new tag group by clicking the plus icon in the upper right. And I'll rename it to "Leased Tag Group". I'll change my mode from direct to leased. And you can see now we have a rate and a leased/driven rate. The leased slash driven rate, is the rate at which the tag data will be fetched when the tags are in demand or being viewed in the client session or designer. And the original rate is the rate that those tag values will be fetched when the tag is not in demand. I'll make this rate a little bit slower. So I'll set it to something like 5,000 milliseconds or five seconds. And then we'll come down to the bottom and click okay. Now I can set my temperature tag to use that new tag group. So I'll change it to my at leased tag group and then come down and hit okay. And then you can see that my temperature tag will now start running at a slower five second rate. Now, if I want to see this run at a quicker rate then all I need to do is drag my temperature tag onto my view here. And I'll have it display as an led display component. And now, because this tag is in demand, it's being viewed on a view. Then we will see that our value updates at the quicker rate. All I need to do to change it back to that slower rate, is remove it from my view. And then now you'll see that in our tag browser, it slows back down. So you can see, this is a very easy way to reduce the load on your resources, when tags aren't in demand.