I believe (I am certain in it) that people in meteo station would not approve this shading. That is why I posted my concern. I believe meteonorm has Perez model implemented in order to split global to direct and diffuse. Unfortunately, I do not have meteonorm, and I need this type of conversion every 2 weeks. I will look at the e+ documentation again. Maybe I didnt see something.
Marko
Energyplus splits the global radiation to direct and diffuse. You may try to measure diffuse by shading your sensor from direct solar radiation
Would be nice to see your measured results. The relationship between the 'Normal' and 'horizontal' components are given in the documentation