Suppose there are two busbar panels, and we want to interconnect them for supplying power to a common load or switching supplies after a fixed interval. In this case, a bus coupler is used to switch the busbar power supply. In case of failure of either of the transformers, busbars, cables or their associated switchgear, a changeover option between the two will be at. So let's start with different bus-bar schemes or systems in an electrical substation. In this type, all incoming and outgoing bays such as lines, transformers, and feeders are directly connected to. A single-busbar switchgear has one main busbar that connects all incoming and outgoing circuits. The design is simple — just one main bus, circuit breakers, isolators, and protection devices.