Hi Andre, In version 6, both tolerance limits are specified, and PVsyst will choose a quarter of the difference between these values. For example, with -3..+3%, it will be 1.5%, and with positive sorting 0..+3%, it will be -0.75% (i.e. a gain). This module quality loss we have to manually enter or automatically PVsyst will take the right value. We actually manually entering this value till now. Please clarify. 'a quarter of the difference between these values' on which basis this calculation?- Please Clarify Thank you