Automatic transfer switch systems prevent costly appliance repairs for homeowners and help businesses avoid expensive downtime. With a history of innovation spanning more than 130 years, ABB has four customer focused, globally leading Businesses: Electrification, Industrial Automation, Motion, and Robotics & Discrete Automation, supported. kage protection units used to distribute electrical power to numerous individual circuits or consumer points. The board typically has a single incomi g power source and includes a main circuit breaker and a residual current or earth leakage protection device. The core function of any distribution. In medium voltage distribution networks, it is important to maintain a high level of reliability.