3VA Molded Case Circuit Breakers Siemens 3VA Molded Case Circuit Breakers are a comprehensive line of MCCBs that cover line protection applications with currents up to 2000A. Siemens 3VA Molded Case Circuit Breakers include 1600A and 2000A frame sizes and comply with global standards and certifications. These MCCBs offer power metering and communication capability with Modbus, Profibus, and Profinet protocols. UL 100% ratings are available in the 1200A and 1600A frame sizes.