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Able to read but unable to write data from MAPS to PLC

Hi all,
I am using Mitsubishi iQ-R PLC to communicate with MAPS. I am unable to toggle bits , write values through Operator Action. I have selected “Enable Online Change” in GX Works. I have also selected “Output Enabled” in Agent Configurator. When I make change in PLC same is reflecting in the MAPS but when I make any change in MAPS, there is no change in the PLC.

Dear Shrinivas
Please make sure that that scan (input) inhibit (input disabled) tick box is unticked in the tag scanning configuration window.

For this - follow the following steps:

  1. Unscan tag
  2. Untick box
  3. Scan tag
  4. close agent configurator
  5. save
  6. test the outcome.

let us know.

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Hi ReVo, I have figured the problem. Its different than what I posted. The issue is I am using a COButton to display value with {0:N0} formatting. But it cant show value more than 1000. And that is why it appears as if its not reading from PLC. When the value is less than 1000 it works fine but when the value is more than 1000 it gets stuck. Any solution for this?

Dear Shrinivas

This depends on the Agent type your tag is.
I will assume that you are using an Analog Agent for this tag.
Please check your Device Span and Engineering Span - Maximum Limits on this tag.

By default they are scaled 1000:1000.
These are user-defined.
Please confirm and let me know.


Yes you are right. I changed the Raw Max and Eng Max values and it worked.

One last question, I want to show this PLC value 1234 as 12.34 Hz in MAPS. I am formatting display value as {0:00.00 Hz}. How do I divide it by 100 and then show?

That is good news.

As for the scaling - there are 3 main options:

  1. Analog agent - make the device span range 100x higher than the engineering span range (recommended)
  2. Expression agent arithmetic - divide the analog value by 100 and then output it to a real agent tag. (also practical)
  3. Script agent arithmetic - divide the analog value by 100 and then output it to a real agent tag. (will work - but is overkill for this simple calc)


1 Like

Thanks a lot ReVo. Option 1 solved my issue.