Provide sustainable services in the rail system to gain maximum benefit both society and the problems of life that is extremely important for both services. Earthing ray leaks, lightning, sudden voltage surges, braking pulses   disable railway system (reaching up to 1500 V DC sensitive systems). The Istanbul Metro Lines is protected against the Lightning and OverVoltage by Yilkomer via surge arrester devices.  Thank all the people of Istanbul TRANSPORTATION AS.