A Toroidal Current Transformer (CT) is a precision device used to measure alternating current (AC) in electrical systems. Its toroidal, or doughnut-shaped, design allows for easy installation by passing a conductor through its center. Toroidal CTs are highly accurate, offering minimal energy loss and reliable performance, making them ideal for monitoring, metering, and protective relays. They are commonly used in industrial, commercial, and utility applications, providing essential data for system optimization, safety, and energy efficiency.