Guano flashover has two forms: one is the flashover caused by the accumulation of insulator surface. However, because birds are separated by multiple segments by an insulator umbrella, the probability of direct flashover is very low. The other is guano slippage insulation falling in the outer vicinity, the direct nucleus leads to short-circuit discharge between the upper and lower gold tools, and no guano traces are left on the sueko, which is also the main form of guano flassing. On the basis of successfully simulating the flashover phenomenon of insulator birds, the department of electrical engineering of tsinghua university has studied the flashover mechanism and flashover conditions of guano, and concluded that the falling moment of guano aberrates the electric field distribution around the insulator, causing air gap breakdown of guano channel at the high end of insulation, thus leading to flashover of insulator. Taking the 110 kv synthetic suozi as an example, the circumference with a diameter of 55cm should be protected by fantian. At the same time, consider the wind guano will fall like a parabola. In actual work, the crossarm area on the top of the tower will be regarded as the key for bird prevention within the range of 30-45° with the insulator string as the base point and the Angle between the two sides. Secondly, the bird thorn to ensure a certain density, the birds completely "plug" outside the protection zone.

    In engineering application, due to the complex type of tower, some key areas of bird protection may be left behind, resulting in the occurrence of abnormal bird damage faults. The  bird spikes above the insulator of the three-phase wire is installed in place, but the bird thorn is not installed on the ground pole above the side wire, which leaves hidden trouble for the occurrence of the fault.