What does the symbol VS 1 in vacuum circuit breaker mean? Is there any essential difference between VS 1 vacuum circuit breaker and vacuum circuit breakers produced by other domestic factories?

V is vacuum, S is source, 1 is serial number. The circuit breakers made by Senyuan Electric Branch were originally produced by Xi 'an Senyuan, Changzhou Senyuan and Beijing Huadong Senyuan. Now they are available in large factories and small factories, and the product quality is mixed. Domestic circuit breaker manufacturers are afraid to make VS 1 and then get their own models to sell.