This book collects fault information and maintenance codes of about 95 series soft starters from domestic and foreign enterprises. Each series includes some specific models of soft starters. This book introduces soft starters' fault information and maintenance codes, corresponding fault troubleshooting methods, so as to provide strong support for troubleshooting soft starters, fast repairing soft starters and quickly checking soft starters' fault. At the same time, this book also introduces basic knowledge and basic skills of soft starter maintenance, as well as maintenance examples and inspection materials. This book is easy to carry and find, concise and practical, and is a quick reference for a wide range of soft starters maintenance personnel, numerical control equipment maintenance personnel, mechanical engineering personnel, related college students, enterprise technical managers and other users.