126kV Current Transformer (CT)

The 126kV current transformer (CT) is core primary equipment used for metering and protection in 126kV power transmission and transformation systems. It is primarily installed at circuit breakers, disconnect switches, busbars, and outgoing feeders within 126kV substations. Based on the principle of electromagnetic induction, it transforms high-amplitude primary currents into standard secondary currents of 5A or 1A according to a fixed transformation ratio. This provides highly accurate current signals for relay protection devices, energy meters, and measurement and control systems. Furthermore, it achieves electrical isolation between the primary high-voltage circuit and the secondary low-voltage circuit, ensuring the safety of secondary equipment and operation and maintenance (O&M) personnel. Ultimately, it serves as crucial foundational equipment for the safe and stable operation of the 126kV power grid, as well as for fair and accurate energy metering.