Insulation class. Diff between a and e

It is the maximum permitted operating temperature of any electrical equipment. The classes are

CLASS A – 105 deg cen

CLASS E -  120 deg cen

CLASS B – 130 deg cen

CLASS F – 155 deg cen

CLASS H – 180 deg cen

The materials used for insulation are cotton, silk, mica products, glass fibre, polyvinyl acetyl, paper, pvc.