I'm trying to build some analysis templates for an element template I created in PI system explorer. At the moment all I want to do is compute a basic calculation using attributes Acetylene, Ethylene and Methane, which are all linked to a PI tag. The calculation I want to perform is Variable1 = 'Acetylene' + 'Methane'.
The error message in the title came up when I tried to evaluate my calculation and now that I've played around a bit it appears I can't even add a number to a single attribute (ie. Variable2 = 'Acetylene' + 6)
How can I fix this issue