FIELD: electrical engineering.
SUBSTANCE: invention can be used in electrical engineering for monitoring resistances in protective earthing networks in specific conditions of potassium mines characterized by high resistance of rocks and inadmissibility of groundwater availability. In the current circuit of the measurement circuit, a reference resistor is used, the resistance value of which is set in Kmultiple times greater than the standardized earthing resistance for a given measurement point in the mine earthing network. Value of controlled earthing resistance is calculated by preset algorithm using values of voltage drop at reference resistor and voltage on controlled earthing. Calculated and normalized values of resistances are compared logically and information signals on grounding state are generated. Obtained signals are used for local signaling. Besides, by means of collection and transmission of signals from all control points, group centralized monitoring of grounding network state is performed.
EFFECT: technical result consists in providing the possibility of continuous automatic monitoring of the value of grounding resistance both in separate points in the network of protective earthing of the mine, and group centralized control.
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