3. Q. Where does the main reservoir pressure begin and end?
A. Begins at the discharge valves in the compressor and ends at the engineer's brake valve.
4. Q. Where does the brake pipe pressure begin and end?
A. The brake pipe pressure begins at the feed valve and ends at the brake pipe side of the triple piston, conductor's valve and at the rear angle cock.
5. Q. What is meant by excess pressure, and where is this pressure carried?
A. Excess pressure is carried in the main reservoir and is the pressure above that in the brake pipe.
6. Q. Why is excess pressure necessary?
A. To insure the prompt release of all brakes and quick recharge of the brake pipe and auxiliary reservoirs.
7. Q. How is the amount of excess pressure regulated?
A. By the compressor governor.