The book “Electrical Instrumentation” serves as a comprehensive guide and reference for professionals, engineers, technicians, and students in the field of electrical engineering and instrumentation. Authored by experts with extensive knowledge and experience in electrical instrumentation, this book offers a deep dive into the principles, technologies, and applications of instruments used to measure and control electrical parameters. The book begins with fundamental concepts, introducing readers to the basic principles of electrical measurements, metrology, and instrumentation. It provides a solid foundation by explaining the theory behind various measurement techniques, including voltage and current measurements, resistance measurements, and frequency measurements. As the book progresses, it delves into the intricacies of modern electrical instruments. It covers topics such as analog and digital instruments, sensor technologies, signal conditioning, data acquisition systems, and the design and calibration of measurement instruments. Special attention is paid to the latest advancements in digital instrumentation, which includes digital multimeters, oscilloscopes, spectrum analyzers, and smart sensors. Practical applications are a significant focus of the book. It illustrates how electrical instruments are used in diverse industries, from power generation and distribution to industrial automation, telecommunications, and electronic design. Real-world examples, case studies, and troubleshooting guides provide valuable insights for professionals facing measurement challenges in their day-to-day work.