The copper bar is also known as the copper bar or copper collecting bar, which is made of copper. The section is the rectangular or chamfer (filleted corner) rectangle long conductor (generally filleted corner copper bar at present, so as to avoid tip discharging). It plays the role in conveying current and connecting electrical equipment in the circuit.

The copper bar is widely applied in the electrical equipment, especially the complete power distribution device; the copper bar is adopted in U, V and W phase busbar and PE busbar in the power distribution cabinet generally; the copper bar is generally marked with the phase color letter sign or applied with the phase color paint during use, U phase copper bar is painted in "yellow", V phase copper bar is painted in "green", W phase copper bar is painted in "red", and PE bus copper bar is painted in "yellow and green".