配电系统中220伏转220伏的变压器叫隔离变压器，隔离变压器的初级、次级绕组圈数是一样的。利用电磁感应原理使得输入、输出电压一样，可以避免触电。

交流电的火线跟大地的电势差为220伏，如果不小心触碰就会触电。因为隔离变压器的输入、输出绕组是完全绝缘的，隔离变压器的次级不与大地相连，任意一条线与大地都没有电势差，只接触一条线就不会触电，更为安全。由于初级、次级完全断开，还可以起防干扰的作用。车床控制、维修电源、压缩机等应用都会使用隔离电源。

Why is a medical isolation transformer safe?

In power distribution systems, a transformer that converts 220 volts to 220 volts is called an isolation transformer. The primary and secondary windings of an isolation transformer have the same number of turns.

It utilizes the principle of electromagnetic induction to ensure that the input and output voltages are equal. Isolation transformers can prevent electric shocks.

In alternating current (AC) systems, there is a 220-volt potential difference between the live wire and the earth, so accidental contact with the live wire can result in an electric shock. Because the input and output windings of an isolation transformer are completely insulated, the secondary side of the isolation transformer is not connected to the earth, and there is no potential difference between any of its wires and the earth. Thus, touching only one wire will not cause an electric shock, making it safer to use. In addition, since the primary and secondary sides are completely isolated, it can also play a role in anti-interference. Isolation power supplies are widely used in lathe control, maintenance power supplies, compressor, and other applications.