Intouch Wonderware reading Flow Meter

Hello,
I have InTouch Wonderware that was reading some flow meters and currently the power has been disconnected from these flow meters.

These meters could be put back into service again so I'd rather not delete the tags from Wonderware

My problem is that Wonderware is reading the last value that was on the flow meter and this is not correct of course, it should be reading zero since there is no flow.

How can I configure Wonderware to were when there is no communication to the flow meter, it will display zero flow and not a false value that is hung at the last state it was polled?

Thanks for helping

Is the DAServer (or IO server on earlier Intouch versions) still connected to the tags?

I assume the flow meters are inputs to a plc and WW is monitoring signal from plc.
Kind of odd...without flow meter connected the plc register should read zero on the input, which Intouch should read....if tag is still viable.

Maybe send a zero signal (voltage or current) to input to plc for flow meter that is no longer connected, untill Wonderware picks it up?
You could also put a button in Intouch to send a "0" to the flow meter signal tag. Use "Touch Pushbuttons>Action" script and using "On Left Click/Key Down" enter Flowmeter_Tag=0;

It is quite common for an HMI that is reading a field instrument via Modbus to retain the last value, as stale that data may be.

Sometimes there is an option to read a discrete value that goes to logic 0 when the unit is no longer powered.

Another approach is to compare values (if floating point) because FP values are noise out in the lower order to-the-right of the decimal point values. A five times repeated identical value is a stale value. No flow is ever that constant.

I read the flow meter into Wonderware through TotalFlow TDS32 program which uses a OPC link to Wonderware.

TDS polls the flow meter to receive the value, which I read into Wonderware
Now that the meter is disconnected TDS cant poll the meter & Wonderware is stuck on the last value it polled previously.

Without deleting the tag in Wonderware is there any scripting ways I can go around this issue?

what happens if you reboot the server? tds32 shouldnt hold the last value after a reboot.... I dont think. I havent used tds32 so I cant vouch for if it pulls the last value from the totalflow database instead of the actual live comm link. in my experience with wonderware, it will startup with the "default" value set on each tag, then as the driver tries to poll it will set the tag value with what is reported by the driver. typically if comm is bad, it will load with zeroes on a fresh reboot. if the driver had already been running, it may use the bad quality last known value. thats why I asked for you to reboot.

NetNathan said:

You could also put a button in Intouch to send a "0" to the flow meter signal tag.
Use "Touch Pushbuttons>Action" script and using "On Left Click/Key Down" enter Flowmeter_Tag=0;

Click to expand...

This should work.
Make sure you check to make sure tag properties for "Flowmeter_Tag" to verify that "read/write" is selected, and not "read only".
Also...make sure "Flowneter_Tag" is not "retentive"...

To solve future issues with false readings......
You may be able to make an alarm on bad or lost signal by using one of the tags "dotfield properties" relating to quality. Then perform a reset to "0" either automatically or manually.
You can see all the "dotfield" properties available for a tag by opening an animation link (like a light or button for example), a script box.....anywhere you can enter a tag.
Enter the tagname with a dot at end. (ie..."Flowmeter_Tag."). Then double click..you will get a popup showing all the dotfield properties available for the tag. Some of these properties are read only.

Thanks so much for your help!!

I realize this is very late but the latest versions of InTouch support a capability know as advanced numeric formatting. This has many capabilities and one of which is the ability to define the value to be displayed when the data quality is Bad.