What happens when a current transformer is disconnected?

When a current transformer (CT) is disconnected from its load while current is still flowing through its primary winding, it can generate dangerously high voltages due to the open-circuit condition. This occurs because the transformer cannot provide a return path for the magnetic flux, leading to a phenomenon known as "saturation." Such high voltages can damage the CT and connected equipment and pose safety risks, which is why CTs should always be short-circuited or properly terminated before disconnection.