A system includes a first group of cassettes, each cassette including a first stationary bar, a first plurality of fixed contact members, and a first plurality of movable contact members, each of which is electrically coupled and rotatably connected to the first stationary bar and configured to contact one of the first plurality of fixed contact members. The system includes a second group of cassettes each including a second stationary bar, a second plurality of fixed contact members, and a second plurality of movable contact members, each of which is electrically coupled and rotatably connected to the second stationary bar and configured to contact one of the second plurality of fixed contact members. The system includes at least one operating mechanism to control opening and closing of the movable contact members. The first stationary bar is coupled to the second stationary bar.