Causes of insulation failure

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Causes of insulation Failure :

 
(a) Cracking of Insulator - Porcelain insulator mainly consists of three different materials like main porcelain body, steel fitting arrrangement and cement  to fix the steel part with porcelain. The unequal expansion and contraction  of porcelain, steel and cement are the chief cause of cracking of insulator .  

(b) Defective Insulation Material -  If the material used for insulator is defective then it gets easily punctured.

(c) Porosity in the Insulation Materials - When porcelain insulator is manufactured at low temperature then it will make insulator porous and it willl absorb moisture from air which reduces insulation.

(d) Improper glazing of Insulator surface - If the surface of porcelain insulator is not properly glazed ,moisture can stick over it and cause insulation reduction.

(f) Mechanical Stresses on Insulator - If insulator has any weak portion due to manufacturing defect it may break from that weak portion due to  mechanical stresss applied on it by its conductor.



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