The isolation transformer is a classification method of the transformer. The isolation transformer also works by electromagnetic induction (ie, Lenz's law). The isolation variation in the flat state is such a thing:
That is to say, we often use 380V AC voltage when repairing TV or electrical appliances, and it is unsafe to use 380V directly from the mains, because its neutral line is grounded at the neutral point of the transformer, so when people touch the fire line and the earth Forming a circuit that can cause people to get an electric shock through human body current. In order to avoid electric shock in this way, the primary and secondary of a transformer are the same (ie, the ratio is 1:1), so that the secondary side is also 380V, forming an isolation transformer, but please note that although it is an isolation transformer However, if the voltage across the secondary ends is reached, the same current will be generated, so it is important to understand that true isolation is only a direct link from the mains.