The DEFECTOMAT systems by FOERSTER were specially developed for quality testing and process monitoring of long products. From hot testing to all bright steel processing steps, the surfaces of semi-finished products made from austenitic, (non) ferromagnetic metals can be tested for defects. The DEFECTOMAT systems operate in a contactless and non-destructive manner in accordance with the eddy current method and are used for detecting short defects, such as holes or localized defects and transverse defects. The systems detect defective materials fully automatically and reliably. Defects can be marked, classified, and automatically discarded. the test speed of up to 150 m/s facilitates 100% testing, even at high production speeds. The systems benefit from low operating costs and frugal energy consumption as well as low maintenance costs, few wear parts, and low use of materials.