Ans: 1. Specially designed to withstand severe operating conditions.
2. Have high short time peak capacity.
3. Class A insulation specially reinforced to withstand stresses of frequent short circuits.
4. Can take overloads as- 50 % for 15 min , 100 % for 5 min , 120 % for instantaneous
5. Impulse withstand voltage nearly 5 times higher
6. To limits the effect of SC , impedance not less than 8.5 % for 10 MVA and 10 % for 12.5 MVA.