High Quality Content by WIKIPEDIA articles! In electrical grids, a power system network integrates transmission grids, distribution grids, distributed generators and loads that have connection points called busses. A bus in home circuit breaker panels is much smaller than those used on the grid, where busbars can be 50 mm in diameter in electrical substations. Traditionally, these grid connections are unidirectional point to multipoint links. In distributed generation grids, these connections are bidirectional, and the reverse flow can raise safety and reliability concerns. Features in smart grids are designed to manage these conditions.