AUGMENTATION OF POWER SUPPLY SYSTEM IN N- S CORRIDOR, UP GRADATION OF NEGATIVE ISOLATORS & DC NEGATIVE CABLES IN TUNNEL SECTION FROM KDMI TO KMUK, RENOVATION OF KMUK CAR SHED, PROVISION OF ETS AND OTHER RELATED WORKS IN NORTH SOUTH CORRIDOR, AUTOMATIC SHORT CIRCUITING BETWEEN 3RD RAIL AND RUNNING RAIL, REPLACEMENT OF OLD ISOLATOR BY MOTOR OPERATED ISOLATOR, REPLACEMENT OF OVERAGED ISOLATORS OF NOAPARA DEPOT & KKVS DEPOT, UNIT PROTECTION OF RECTIFIER AT DUM DUM TSS, RABINDRA SAROBAR TSS & PARK STREET TSS, AUGMENTATION OF POWER SUPPLY SYSTEM AT SUBSTATIONS FROM KSHY TO KCEN & PROVISION OF CCTV IN ELECTRICAL SUBSTATIONS OF NORTH SOUTH CORRIDOR IN METRO RAILWAY KOLKATA