We are having two issues when downloading a control module. All modules mentioned below are assigned to the same simplex SX controller, so it's not an inter-controller or redundancy issue. DeltaV version is v12.3.1.
All our CMs have a reference to a Boolean (without status) parameter to the Unit Support Module, like this:
In addition, the USM itself has a reference to bring #THISUNIT# as a parameter in the module (this is just an Input Parameter which is an ext.ref).
Now, this is what happens when we download:
First question is: what is Attribute Override Error? What is the problem with the reference?
The second, more important question is: why do our control modules have MODBAD when we download the USM? What it Module Error 32? It only lasts one scan and it is not happening consistently on all CMs, even though they all reference USM/UNIT_MAINT exactly the same way.
Since we noticed this, we could also reproduce it on other modules having external references. When the referenced module is downloaded, sometimes we get Module Error 32, sometimes Module Error 64.
Additionally, it also impacts phases. E.g this condition in the Hold Monitor of a phase became TRUE momentarily after downloading the USM, sending the phase to hold:
The reason was some kind of read error, because setting the ERROR_OPT of the block to False solved the issue, it does not trigger. (needless to say, the HELD parameter this condition is monitoring was false all along)
Cold Restart on the controllers was Disabled and Enabled (maximum time) and Disabled again in the last couple of weeks. Could it be related?
We'll open a call with GSC, just wanted to check if someone can help us faster.