Disconnector Blocking Control Device is a locally produced system designed to prevent personnel errors when operating with disconnectors, earthing switches, short-circuiting switches and other switching devices in switchgears of 6-750 kV voltage of existing and newly constructed power plants and subplants in federal and interregional grid companies, oil and gas industry, housing and communal services of cities, metallurgy and other energy-intensive industries. The system implements the following functions: a) control of position of switching devices (switches, disconnectors, grounding knives if they have manual or electric drives), as well as monitoring of the state of the block locks; b) indication of the current position of switching devices and the state of the block locks; c) control of locks based on the logic cheme and data on the position of switching devices; d) prevention of wrong actions in the production of operational switches of disconnectors and grounding knives.