abcpvpv

there are more than 4000 pv 3dface in dwg. 1 impert dwg into sketchup 2 export to dae 3 import dae into pvsyst most of the them are ok. but some of the pv 3d face is splited to two triangle. why ? if i delete 3500 face. only export 500 faces (include the wrong faces just now) to DAE. then import 500 faces into pvsyst. all of them is ok.....。they are not splitted to 2 triangle.

terrain there are many CAD point (x,y,z) of the terrain. how to import them to PVSYT

in cad ,x is east, y is north. in pvsty, x is west, y is south. if import cad (convert to dae ) to pvsyst, all of the pv(3d face) is rotated 180 degree. how should i do ?