Unit Over Range / Unit Under Range

3 posts in this topic


I installed many I/O Units on my ECC203 and I was checking the parameters each unit displays. I found something that could be interesting to know about but I have 0 skill checking this info on the manuals if there's any.

What I'm talking about is on the Configuration and Setup / EtherCat / Node# / Unit# -> Edit, between all the parameters :

  • "Event Level Setting/Event 1" : Unit Over Range
  • "Event Level Setting/Level Setting of Level 1" : Observation / Minor fault
  • "Event Level Setting/Event 2" : Unit Under Range
  • "Event Level Setting/Level Setting of Level 2" : Observation / Minor fault

First of all, What is this exactly? I understand this is for the range of resolutions for example between -15000 to 15000 points on 30000 resolution units, right? So a internal signal checks if this is true of false if the analog I/O goes over or under those points?

How can I interact with this on the Ladder? Can I create a Global Variable that shows a bool value asociated to this Event?

Can I Edit the Under Range value to trigger whenever it is below 0 points instead of -15000 points as described in the above example, in case that is how it works?

What else can you guys tell me about these Events?


Thank you

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The Observation and Minor Fault is referring to a controller Event. If you choose Tools > Troubleshooting, you can view Controller Event Log to see all these logged Events. A Minor Fault will flash the Error LED at 1 second intervals. An Observation will not light the Error LED at all but will still log the Event. I probably haven't used this function to its fullest capability and I don't know much more than that. You can access this Troubleshooting window from an NA5 screen. That's nice.

I think you understand the Over / Under Range. Unfortunately, I know of no way to get the information into Ladder. I've looked for this myself. To the best of my knowledge, the tags your are able to create will be found in the I/O Map. I created my own Over and Under Flags by using standard comparison instructions in Ladder. In this way, you can easily compare to 0 instead of -15000.

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Alright, thank you, I had already a variable that stores the I/O value to compare these later. But I thought It could be an interesting feature if Omron could control automatically these range events by assigning specific unit variable.


Edited by Artz

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