Main circuit breaker for electric locomotive

The utility model relates to a main circuit breaker for an electric locomotive, which is composed of an air storage cylinder, a pressure relay, a main valve, a delay valve, a starting valve, a transmission air cylinder, an isolating switch blade and an arc extinguishing chamber. The utility model is an improvement on the prior main circuit breaker of an electric locomotive. The wind collecting port of the starting valve is provided with a datum rib. A static contact of the arc extinguishing chamber is directly soldered, and the spring of a movable contact is formed by winding a plurality of small steel wires. An automatic water discharging device is arranged on a wind storage cylinder. Therefore, the fully automatic multi-function silicon wafer corrosion machine prevents the blocks of the main valve from being smashed, reduces contact resistance and increases the mechanical life of the main circuit breaker. The utility model also avoids explosion of a supporting insulator, the burnout of a main valve and a delay valve, the breaking of a porcelain insulator, explosion of non-linear resistance porcelain insulator, etc.