Dear Andre', I typically always check the imported values and ensure they match with SCADA values. There is no issue with that. Values such as Irradiance, ambient temperature and wind speed are fine. Also, the Eout Inv and Egrid values when verified using graphs and tables appear good. It's only that once the simulation is performed, I see a significant amount of Egrid data is lost and is shown as "Inverter loss over nominal inv power". However, I am not sure why that would happen and we are modelling the inverter correctly. Also, I am not importing any PV voltage or current values or any other values Is there a particular reason why PVsyst would show zero values for particular hours of the day in the CSV file that we review once the simulation is done. Please find attached loss diagram where you will find a significant amount of data is lost over nominal inverter power. Thank you for your help, Saurabh Sample result file of measured data analysis