What to bring about transformer sky to carry loss and the account that hold elec

What to bring about transformer sky to carry loss and the account that hold electric current to increase for nothing to basically have?

Answer: Basically have the following reason:
1. silicon steel piece an insulation is undesirable;
Silicon steel of part of Zhong Mou of 2. magnetic circuit piece between short circuit;
3. wears core bolt or pressing plate, go up yoke and attaint of other part insulation, form short circuit;
The silicon steel in 4. magnetic circuit piece shake occurrence air gap, increase magnetoresistive;
5. coil has short circuit of spur track of paralell connection of v/LIT all over the ground occasional;
The turn number in spur track of 6. each paralell connection is not same;
How does 7. winding circle number is obtained incorrect.