JUSTIFICATION OF 6 KV POWER MINE CIRCUITS INSULATION RESISTANCE CONTROL METHOD
The parameters of distribution circuits with the voltage of 6 kV have been analyzed. Their significant capacity against earth has been noticed, which leads to ground fault currents in emergency situations, which exceed significantly the requirements of reference documents. The known devises for selective protection react in fact on metallic phase to ground short circuit. Forced desensitization of these devices is caused by constantly changing circuit parameter due to changing of its configuration, necessity of offset from asymmetry voltage, incorrectness of compensating device settings. The advantage of protection created on basis of application of control current on isolated operating circuit has been shown.