i am trying to get the value, not setting it. The value is placed already at the start of the model. There are 3 objects: V60, XC40 and V40. And the V60 has to go a slight different route. The attribute is already defined in the MU tabs on the library and doesn't change along the process.
if you only have three objects then you could create three global variables and store a link to the objects there (e.g. exit control of the source). Then you can access the parts everywhere in the model via the variable.
if you only have one instance of the MU, you can directly access the MU with e.g.
freelance simulation specialist