Status Code as result of Write Tag

[alattanzi]

Good morning everyone,

I am using the Client Ver 1.0.5 library to communicate with PLCs, mainly Siemens, which act as servers.
I have a question regarding the StatusCode returned by the write function. When the value Good is returned, does this indicate that the tag value has been written correctly to the server? Or anything else?

I ask this question because, occasionally and randomly, even though a Good status is received, the tag is not updated on the PLC. Has this ever happened to you?
Andrea Lattanzi

[kevinherron]

All you can take away from it for sure is that the Server is indicating the write succeeded.

This kind of problem comes into the support department at work from time to time, with OPC UA or with other protocols used to communicate with PLCs. It's nearly universally the PLC logic resetting the value.

I know, I know - you don't think that's what it is. You're sure there's no logic. Literally every person ever has thought and claimed the same, and it almost always turns out that there is indeed some logic resetting the value, if it's not something silly like writing to an input that OPC UA says is writable but in the physical world is not.