State the temperature with standing capacity of following class-insulating material class Y, class A, class B, class E. Also state two examples for each.

State the temperature with standing capacity of following class-insulating material class Y, class A, class B, class E. Also state two examples for each.
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1 Answer

Answer :

S.No
Class of Insulating material
Temperature withstanding capacity 0C 
Examples
1 Class ‘Y’
900C
Cotton, Silk paper and similar organic materials neither impregnated nor immersed in oil, rubber, PVC  
2 Class ‘A’
1050C
Impregnated paper, Silk, cotton and polyamides resins
3 Class ‘B’ 
1300C
Inorganic materials ( mica, fiber, glass, asbestos) impregnated with varnish and other compounds
4 Class ‘E’
1200C 
Cotton fabric, synthetic resin enamels. Paper laminates and Powder plastics
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