Which device is used to connect an oil switch to a high voltage circuit?

The device that connects an oil switch to a high voltage circuit is a current transformer. Current transformers are critical components in high voltage applications because they allow for the measurement and monitoring of electrical currents safely. They step down the high voltage current to a lower, manageable level that can be easily measured or utilized by control and monitoring systems.

In the context of an oil switch, which is often used for switching operations in high voltage environments, a current transformer serves the crucial function of sensing the current flowing through the circuit. This information can then be used to provide feedback for protective relay systems or control mechanisms, ensuring that operations can be conducted safely and effectively.

Other devices like voltage regulators, capacitor banks, and relay switches serve different purposes in electrical systems. Voltage regulators manage voltage levels, capacitor banks store electrical energy and release it when needed, and relay switches are used for controlling the electrical circuits' operations rather than directly interfacing with high voltage circuits in the manner that a current transformer does. This distinction reinforces the role of current transformers in safely bridging the operational aspects of an oil switch with high voltage circuits.