Help current and future technicians gain a thorough understanding of today's electronic variable speed drives with this one-of-a-kind practical guide. ELECTRONIC VARIABLE SPEED DRIVES, 4E provides the information essential for mastering DC and inverter drive technology. Using a logical structure, this book introduces fundamental drive circuits before presenting more complex drive circuits. This new edition highlights the most current technology advances for drives. The authors use their extensive industry and teaching experience to present theory in a clear, straightforward manner with an emphasis on both troubleshooting and maintenance. New hands-on activities in this edition provide additional practice using the Allen-Bradley PowerFlex 70, while numerous waveform schematics guide readers through operating different types of drives and interpreting their circuitry. Specific chapters focus on digital regenerative DC drives and frequency inverters as well as mechanical and electrical installation, set-up, tuning, programming, operating, and troubleshooting of each drive. Depend on this concise, yet thorough, book to present the information professional technicians need for success.