For each family category, there are certain built-in parameters such as ‘Model’ and ‘Description’ and in the case of the Light Fixture category there is also ‘Lamp’ or ‘Coefficient of Utilization’. Furthermore, for the Light Fixture category, additional parameters are added when ‘Light Source’ is checked in the Family Category and Parameters dialogue. I call these parameters the ‘Problem Children’ because their values are tricky to control. The difficult thing about building a light fixture that represents a manufactured product is knowing how to best do this.
These parameters are held inside of buttons, which makes controlling them via formula impossible. The only alternative to formulas is to utilize Types or Type Catalogs. Revit Quirk Alert: the names needed in a type catalog to control these parameters are different than the actual parameter name.
“The Problem Children”
I worked on a family with well over 500+ types when all of the options were accounted for, so a type catalog was the best solution to make sure only the necessary types were loaded into a project. I had struggled with the parameters for a while before coming across the solution, which is this:
For “Initial Intensity”, the type catalog needs to use the name “Luminous Flux”, and for “Initial Color”, “Initial Color Temperature” has to be used. When data type and unit are added in, that translates to:
Initial Color Temperature##Color_Temperature##Kelvin