An electrical transformer and a current transformer are both types of transformers used in electrical power systems, but they serve different purposes.

An electrical transformer is a device that transfers electrical energy from one circuit to another through electromagnetic induction. It is typically used to change the voltage level of an alternating current (AC) power supply, either to step up the voltage for long-distance transmission or to step down the voltage for local distribution.

A current transformer, on the other hand, is a type of transformer that is specifically designed to measure the current flowing in a circuit. It is used to provide an isolated secondary current that is proportional to the primary current in the circuit. This allows the current to be measured and monitored safely and accurately.

In summary, the main difference between an electrical transformer and a current transformer is their primary purpose. An electrical transformer is used to change the voltage level of an AC power supply, while a current transformer is used to measure the current flowing in a circuit.