Screw flat connection 3 pieces Accessories for: 3VA1 400/630 3VA2 400/630 Connection technology for 3VA molded case circuit breakers. The connection technology of the 3VA molded case circuit breakers enables an uncomplicated and convenient way of commissioning the 3VA molded case circuit breakers in accordance with all installation requirements. www.siemens.de/3VA. Siemens offers a comprehensive portfolio of protection, switching, measuring and monitoring devices, distribution systems as well as switches and sockets for safe, efficient electrical infrastructure in buildings and industry.