What is the functions of bus?

Bus bars are used in Motor Control Centers (MCC) and high voltage switch gear. These copper bars are used in place of wire that would be hard to bend and fit into tight cabinet spaces. The copper bars are easily formed into odd shapes toaccommodate connections of the incoming power source to internal equipment. The bars are easily extended if another section has to be added on for future expansion. In an MCC, if more motor sections are needed the new panel is just bolted to the old bus bars for a continuation of the power to the new section. Because of the amperage of some equipment, single wire just does not have the capacity to handle the current.