Technology of safe Drives

During the last 20 years safety technology has brought a lot of advantages for mechanical and electrical machines and equipment. The number of injuries or even of killed person could be reduced by a factor of more than 10. During the operation phase of machines all existing risks have nearly disappeared. Nevertheless the life cycle phases of test, maintenance, or retrofit are still dangerous. Persons, who are in touch with machines or parts of machines run the risk of being injured, if sudden unexpected movements happen. The only possibility to avoid such unexpected operations is the use safety related drives. The principles and technologies of such drives are described in the following paper.