Three-phase transformer Precautions

Together into a single-phase three-phase transformer connection group, you can not use YNy0 connected three-phase group. Three-phase shell-type transformers can not be used YNy0 connection. 
Three-phase five-column core transformer must be used YN, yn0, yn0 connection method, the transformer must be connected into the fourth winding angle connection, it does not lead to early (electri cenergy meter structures do not succeed drawn in this case). 
5) Different coupling transformer parallel operation group, the general rule is to join groups must have the same label. 
6). Distribution transformers for multi-mine area, we can use Yzn11 connection, when using the z connection, the impedance voltage connection of different algorithms and Yyn0 while z connection winding Copper weight to more. Yzn11 lightning distribution transformers connected in better performance. 
7) three-phase transformer core box using the four volumes when they can not be used YNy0 connection. 
8) The above are used for air circuit breaker connection, such as the export shall be required to supply the appropriate connection and connection symbol. 
9). Generally within the high voltage winding has a tap and tap-linked. Therefore, when the tap selection (including load tap changers and mcb circuit breaker switch), you must pay attention to the transformer connection and tap connection compatible (including connection, test voltage, rated current, each level voltage, voltage range, etc.). Right YN-connected OLTC used load tap changers concerned, but also pay attention to the mid-point must be able to lead.