The primary task of isolation transformer is to electrically insulate the primary and secondary windings, so the most basic requirement for it is to ensure the insulation performance of the primary and secondary windings. However, transformation is not its primary task. Most isolation transformer do not transform, that is, the turns of the primary and secondary windings are equal. For example, the pulse transformer used in the thyristor DC speed control system to prevent high-voltage intrusion into the pulse numerical control device is also a typical example.
Special features of isolation transformer:
① Primary grounding, secondary not grounded; ② There is also an isolation layer in the first level line compartment! This isolation layer is connected to the primary grounding terminal, which means the isolation layer is grounded. Therefore, the secondary terminal is isolated from the power grid and electrostatic field!
Due to the secondary not being grounded, the output end does not form a circuit with the ground, so there will be no electric shock when a single end of the human body contacts the output. Moreover, due to electrostatic isolation, static interference and breakdown are avoided during secondary operation!
