CT Transformer

The Current Transformer (CT) is a crucial component in electrical power systems, used to measure and monitor alternating current (AC) in high voltage and current circuits. It is designed to step down a high current input to a smaller, more manageable current that can be safely measured and monitored by various protective devices and instruments.

The primary function of a CT is to provide an isolated secondary current proportional to the primary current flowing through it. This secondary current is accurately scaled down according to a specified turns ratio, typically in the range of 100:1 to 5000:1. By stepping down the current, CTs allow for safer and more precise measurements and monitoring, preventing damage to instruments and minimizing the risk of electric shocks.

CTs consist of a primary winding and a secondary winding, both wrapped around a magnetic core made of high permeability material. The primary winding is connected in series with the circuit carrying the current to be measured, while the secondary winding is connected to the measuring or monitoring device. As current flows through the primary winding, it creates a magnetic field that induces current in the secondary winding based on the turns ratio.

CTs are typically categorized based on their construction and application, such as window-type CTs, bar-type CTs, bushing-type CTs, and more. Each type has its own advantages and is designed to cater to specific requirements of different electrical systems.

In addition to current measurement, CTs also serve various protective functions in power systems. They are extensively used in protective relays and circuit breakers to detect faults and abnormal conditions, such as overcurrent, undercurrent, and short circuits. By providing reliable current readings, CTs play a crucial role in ensuring the safety, stability, and efficiency of electrical networks.

In conclusion, CT Transformers are essential devices in electrical power systems. They provide accurate and scaled-down measurements of AC current, allowing for safe and efficient monitoring of electrical circuits. Whether used for measurement or protection, CTs are vital in maintaining the reliability and safety of modern power systems.