The Factory Acceptance Test (FAT) is a quality assurance process prior to the delivery of a product. Once production of the product has been completed, it is checked by the manufacturer (acceptance). If no defects are found in the product or machine, it can be accepted. However, if defects are found after the Factory Acceptance Test has been carried out, these must be rectified by means of subsequent performance before a new Factory Acceptance Test is carried out. It is possible to carry out a FAT until freedom from defects can be guaranteed. The Factory Acceptance Test is carried out on the basis of an acceptance protocol in order to provide the customer with a transparent insight into the implementation. In the field of mechanical engineering, the factory acceptance test is an essential part of quality assurance and should be carried out for every system before commissioning.