Ruslan

Dear unilhexio , I'm found error. Its convertation rad-grad and grad-rad. I'm forgot multiply Pi() for grad to rad. and our formulas and pictures is same : θ = arctg ( sin 36º / (9/3.3 - cos 36º )) = arctg ( 0.58779 / (9/3.3 - 0.809))= arctg (0.58779 / 1.91827) = arctg (0.3064) = 17.04º Many thanks for Your time, Best regards, Ruslan

Dear unilhexio, Our formulas is same. My dont has expression L-cos β. Only Pitch/L - cos β. θ = arctg ( sin β / (Pitch/L - cos β)) = arctg ( L*sin β / (Pitch - L*cos β)) and gives same results (Im checked out now) Please give me your arguments and results will be same. For example I'm calulated : L=3.3 m Pitch = 9 m β = 36 degree. for my formula θ = 20.38 dergree, for yours formula θ = 20.38 degree, PVsyst gived 17.2 If Yours result is different, please write me to eynesr@gmail.com, I will send You my excel - file with all calculations. Best regards, Ruslan

Dear unilhexio, Our formulas is same : L*sin β / (Pitch - L*cos β) = L*sin β / L ( Pitch/L-cos β ) = sin β / (Pitch/L - cos β ) Please give another variant. But if You and me have same formulas, error in the PVsyst?

Please help me find my mistake with calculation of Shading limit angle or give formula for it. For horisontal basis I receive formula : θ = arctg ( sin β / (Pitch/L - cos β)) where β - Tilt of table L width of table = const = 3.3 m (2 portrait modules) My calculation for θ (Pitch, β), degree : θ (5, 30) = 54.7 PVsyst : 38.0 θ (5, 36) = 64.0 PVsyst : 40.1 θ (9, 30) = 17.1 PVsyst : 15.2 θ (9, 36) = 20,4 PVsyst : 17.2 θ (11, 30) = 12.7 PVsyst : 11.5 θ (11, 36) = 15.2 PVsyst : 13.2 looking forward to hearing from any who knows why I receive different results. Regards, Ruslan