Explain the requirements of good insulating material.

Explain the requirements of good insulating material.
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Requirement of good insulating material are: i) Electrical ii) Mechanical iii) Thermal iv) Chemical (i) Electrical requirement: A good insulating material should have high resistivity and low leakage current. It should have high dielectric strength and small dielectric loss. (ii) Mechanical requirement: A good insulating material should have sufficient mechanical strength to withstand vibrations. (iii) Thermal requirement: A good insulating material should have small thermal expansion to avoid damages, It should be non-ignitable and self extinguishable. (iv) Chemical requirement: A good insulating material should be resistant to oils, gas, fumes acids and alkalies. It should not absorb water as water reduces insulation resistance and dielectric strength.

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