three-phase transformer 

three-phase transformer The principle of three-phase transformer and isolation transformer is the same as that of ordinary transformer. All by electromagnetic induction. Isolation transformer generally refers to 380V/380V, 400V/400V transformer. Because the secondary is not connected. There is no potential difference between any of the secondary lines and the ground. Safe to use. Often used for maintenance. Isolation transformers are not all 1:1 transformers. The power source