Wonderware & Siemens Step 7 Issue

I have some Siemens S7 PLCs connecting to a Wonderware Intouch 7 installation. I can pull of a VAT in Step 7 on a 2nd computer and enter in some values and they will instantly be reflected on the Intouch screen.

Other values won't change on the Intouch, even though I set the VAT to constantly load the values. I opened up the WWCLIENT and tried to view the same tag and it shows that the value wasn't updated.

If I change the value in WWClient, I can see it reflected on the Step-7 computer, and in the InTouch program.

Any ideas of what might be causing this? Could it be a PLC problem?

Pardon the language that I used in this post. I'm fairly new to this stuff, so my lingo might not be correct.

If the PLC is running and it is programmed to put a value into a word that you are changing, then the word will change to what the PLC is writing to it.

The VAT table only allows you change a value, it cannot over-rule the PLC if its code is writing to the word.

Why would my WWClient be able to update it then? Albeit, only for a second, but it still updates it. I can't get the VAT to update it when it is set to modify it every cycle.

On a similar PLC setup I worked on a couple weeks ago, I was able to make these changes. This is just weird.

I do appreciate the help, though!

Are you sure it is updating it for any longer that the VAT table. The HMI will store the info its sending down and display that until its reads back from the PLC.

You don't get when updating from the VAT as the HMI has never seen the change.