In post-consumer or post-industrial plastic wastes, like PP, PE, LDPE, HDPE, PS, EPS, ABS, PVB, soft PVC, many contamination type can be found such as iron/steel, wood, paper, textile fibres, Un-melted plastics, aluminium, sand, copper, stones, almost others.by the contaminations are constantly increasing and the traditional (manual) screen changers are not able to deliver a good quality of the final product.