Normally generators are cooled by hydrogen gas. A cooling system consist some hydrogen cylinders, two pressure regulating valves, two isolation valves and a manifold.
Working principle:
Ø Hydrogen gas is supplied from gas cylinders.
Ø Gas pressure is maintained at 100-125 psig by the 1st pressure regulating valve.
Ø Gas pressure is maintained at lower value of 30 psig by 2nd pressure regulating valve.
Ø Two insulation valves are used for insulation the supply.
Ø Finally hydrogen enters into generator through a manifold and cools the entire temperature.