Hi, I am having a similar problem. I'm using the Sunpower X20-250 and the Sunpower X21-345 panels, however both are giving the message "Invalid PV module: please check its parameters." The Definition of a PV module for these panels gives the error, "The single cell mpp voltage is 0.59 V, (it should be between 0.45 and 0.57) Please check the number or cells in the series or the." At which point the error cuts off. I have verified the data with the manufacturer. The X20-250 has a Vmpp of 42.8 with 72 cells which gives 0.59 Vmpp for a single cell. The X21-345 has a Vmpp of 57.3 with 96 cells which gives 0.60 Vmpp for a single cell. Is it just not possible to model these panels in PVsyst? Thanks, Cait
