And isolation transformer winding vice side is not connected to the earth, it's any two lines (the original vice both sides) and the earth between the potential difference. People touch any line will not be electrocuted, this is why the isolation transformer has become a safe power equipment. Isolation transformer commonly used in electronic tubes and high voltage electronic equipment, as well as for the maintenance of the power supply. According to the use of the basis can be divided into two kinds, one is to prevent electrocution accidents and the power supply to isolate the safety of the power supply; the other is the isolation transformer can also be isolated on the electromagnetic interference signal.
Specifically, then you can elaborate on the isolation transformer is how to avoid the risk of electric shock, which can be based on the isolation transformer process and technology, according to Ohm's law, the higher the voltage, the higher the current. Therefore, there has long been a professional assumption that if it is possible to limit the voltage that may be applied to a person to a certain range, so that the current through the human body does not exceed the permissible range at this voltage. That's why there will be the back of the transformer's safety voltage limit, the limit can be in any operating conditions, any two conductors between the highest possible voltage value. In recent years, China's emergence of relevant standards, the limit value of the effective value of the frequency voltage of 50V, DC voltage limit value of 120V. then in accordance with the above theory, process and technology can be considered, in general, in the case of equipped with a speed disconnect to prevent electrocution of the protective device, the permissible current of the human body can be considered by 30mA.