Main Reservoir
For shortage of compressed air pressure MR are provided on this loco. In WAP-7 & WAG-9 loco, Two MR and one AR is provided in machine Room in vertical manner. Capacity of MR is 450 liters. Drain coc is provided below each MR, which can be operated from machine room. In WAP-5 MR are located in under truck and each MR having capacity of 240 liters.
In dead loco AR is charged by BP pressure of Live loco provided that coc 47 should be in open condition. This AR pressure is utilized for conjunction loco braking and Parking brakes.