Combined method for preventing unauthorized supply of voltage to the 0.4 kV electrical network

Unauthorized supply of voltage to rural electrical networks of 0.4 kV is one of the causes of electrical injuries. Its reverse transformation to a voltage of 10 kV at 10/0.4 kV transformer substations increases the risk of electric shock to people. Possible points of supply of unauthorized voltage to the 0.4 kV network have been identified. These are both buses of transformer substations, as well as sections of power transmission lines, internal consumer networks. Existing methods for preventing unauthorized supply of voltage are considered, which involve blocking the possibility of reverse transformation at 10/0.4 kV transformer substations by disconnecting the input switching device of the substation, or switching devices of outgoing 0.4 kV lines. It has been revealed that their use does not reduce the risks associated with the presence of unauthorized voltage in 0.4 kV power lines. A combined method of signaling and preventing unauthorized supply of voltage to the 0.4 kV network is proposed, which consists of using a set of devices in the 0.4 kV network, such as input-metering-distribution devices, sectioning devices, signaling devices and blocking reverse transformation, preventing the supply of unauthorized voltage to various sections of the 0.4 kV network and signaling of the presence of unauthorized voltage.