After defining a scheduled setpoint manager in a plant loop with type of control variable unspecified, the osm file can be saved but not any more re-loaded by OpenStudio: Trying to open the osm file leads to an unhandled exception, as you can see in the attached screen shot.

After defining a scheduled setpoint manager in a plant loop with type of control variable unspecified, the osm file can be saved save but not any more re-loaded by OpenStudio: Trying to open the osm file leads to an unhandled exception, as you can see in the attached screen shot.