This unique text fills the need for a convenient, single-volume reference source on the electrical theory that is the foundation of an electrical utility system. The second edition includes updates to many technical points, describes the equipment and situations that lineworkers deal with daily, and features information on safety. The thorough explanation of theory increases the lineworker's knowledge of the system being operated and maintained. The material is presented in a chronological order, taking the reader from an overview of power systems through current technology affecting the operation of electrical utilities.