1. There are certain differences in the structure between them. The current transformer is generally made of thick wire. It should be used in series with the load that measures the current, and the voltage transformer is a step-down transformer. It is necessary to go around many main lines and connect to the high-voltage power grid to be used.
2. Short-circuit faults are allowed on the secondary side of current transformers, but open-circuit faults are not allowed, while voltage transformers are just the opposite. Open-circuit faults are allowed on the secondary side, but short-circuits are not allowed.
3. Their functions are also somewhat different. The voltage transformer is mainly used to proportionally switch the high voltage to a lower level secondary voltage, and it is generally used in conjunction with a metering device.
4. The current transformer is to ensure the safe operation of the power system. It monitors and measures the operation of power equipment. Generally, it cannot be directly connected to one-time high-voltage equipment, so there is a big difference in their functions.

Notes on current transformers and voltage transformers:
The current transformer cannot be opened for the second time during operation. If the second time is open, then its iron loss will be large, the temperature will be very high and burned, and finally there will be a danger of electric shock.