Error writing to Siemens tag

Having the same issue, did you ever get it figured out?

Can you provide more details about the problem you’re having? Error messages, versions, etc?

ignition 7.9.10

error message attached

checked obvious stuff like read/write enabled, restart gateway etc.

Even on UA expert I can write to the json without any issues

I’ve moved this to its own topic because it doesn’t seem related at all to the one you posted in.

It looks like you have an OPC UA connection to the built-in UA server in an S7-1500, is that right? And it looks like you’re using the UA Next module too, since you were able to subscribe to the HMIrw struct?

yes, that is correct

What version of the OPC UA Next do you have?

Based on the screenshots I can’t see any reason you shouldn’t be able to write to the HMIrw tag as long as the JSON is valid, so we may have to do some digging and upgrading here…

I don’t have access to the gateway at this moment to check. I will let you know as soon as I can.

JSON seems to be valid as I can write to it from UA Expert.

Need to verify all my settings are valid on ignition side - just not totally sure what they should be.


Hi kevin,

Can you send me the latest opc ua next module, thanks

Hi Kevin,

Could it be an issue because I am using a remote tag provider?

That shouldn’t matter in the end, but it’s good to know because you’ll need to be on that remote gateway to look for any versions, do troubleshooting, get logs, and do any upgrades.

Do you have suggestions where I can start troubleshooting this? The log is not telling me anything useful besides type mismatch

You’ll need access to the gateway that actually has the OPC UA connection to the PLC.

The first thing to do is just upgrade the OPC UA Next module on that gateway to the latest version:

If that doesn’t work we’ll probably need to enable some loggers and possibly get a Wireshark capture.

Hi Kevin,

I have done that, which loggers should I enable?