The aim of this Master Thesis is to make a study of the cost reduction possibilities of the secondary equipment of SION Vacuum Circuit Breaker from Siemens AG. The secondary equipment of a circuit breaker consists of several auxiliary devices –usually electronic- which are necessary for operating and controlling the breaker. Regarding the most important requirements for the new M3 price driven market which are Price reduction and Standard technology, a study on the current situation and possible future designs of the main devices of the secondary equipment of the SION Vacuum Circuit breaker has been done. Besides the SION Circuit Breaker analysis, nine competitors of Siemens have also been analyzed to get an idea of what and how other companies are doing for the same functions of the breaker. Thus, this study ends in some conclusions of which the most efficient way of design in terms of cost of a certain device is and where the market is going to while fulfilling the standards and requirements demanded.