State failure phenomena observed in insulating material. State four reasons for failure of gaseous and solid dielectric materials.

State failure phenomena observed in insulating material. State four reasons for failure of gaseous and solid dielectric materials. 
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1 Answer

Answer :

Failure phenomena in insulating material means the dielectric property fails :

 The dielectric failure mean the dielectric strength of insulating material reduces due to high voltages or high temperature observed in insulating material and therefore decreases insulation resistance .

Reasons for failure of gaseous and solid dielectric materials:

1. If the system voltage increases more than breakdown voltage for some interval then there are chances of dielectric failure

2. Long time partial discharge in solid insulator will create dielectric failure.

3. Due to super heating of dielectric material i.e. due to heavy load or over load temperature increases and dielectric failure occurs.

4. Due to lighting surge there may be possibility of dielectric failure.

5. Due to short circuit or ground fault there may be possibility of dielectric failure.

6. Due to poor maintenance of insulating material there may be possibility dielectric failure 
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