Isolation transformers are divided into single-phase and three-phase series, the main role is to isolate the power-using equipment and the power grid, generally used for security occasions or anti-interference requirements of the occasion, the power-using equipment and power supply without direct electrical contact. Usually, an isolation transformer is a 1/1 transformer. The secondary of the isolation transformer is not connected to the earth and there is no potential difference between any two of its wires and the earth. A person touching either line will not be electrocuted, which makes it safer. Secondly, the isolation transformer effectively plays a good filtering role on the input side of the transformer (the power supply voltage supplied by the grid). It provides a pure supply voltage to the equipment.