Knife switch is a manual power distribution electrical apparatus. Mainly used for isolated power supply or manually connect and disconnect the AC and DC circuits, can also be used for less frequent making and breaking below the rated current load, such as small motors, electric stove, etc. Knife knife switch is the economy but a knife switch with low specifications. Knife switch, also known as the on-load switch. It is mainly: porcelain handles and operations linked to the moving contact tool, the static contact holder, fuse, inlet and outlet connection, these conductive parts are fixed on a China plate, and cover with plastic cover. So when the knife closed, operators do not touch live parts.