method for measuring insulation resistance in u043du0435u0437u0430u0437u0435u043cu043bu0435u043du043du043eu0439 mains dc and for localization of short circuit to earth and u0434u0432u0443u0445u043fu043eu043bu044eu0441u043du043eu0435 device input current

摘要

FIELD: measuring equipment.SUBSTANCE: invention relates to measuring insulation resistance in an ungrounded DC electrical network and localizing an earth fault. Essence: two-pole current input device (12) is connected between negative terminal (2) of the network and ground terminal (8) or between ground terminal (8) and positive terminal (3) of the network. Bipolar device (12) has capacitance (20) and diode (15). Current is introduced into the network and the state of the network voltage with respect to the ground terminal is maintained to approximate the operating conditions in the absence of an earth fault. Insulation resistance of the network is defined as the ratio of the DC voltage measured between two terminals (13, 14) of the bipolar device and the DC current flowing through the device. In networks with earth faults through a large resistance, the closure is localized by maintaining a restored voltage and monitoring the DC current introduced into the network from the device.EFFECT: providing a rapid measurement of the insulation resistance in live ungrounded DC circuits with a large capacitance relative to the ground, the ability to determine the location of the closure through a high resistance or several closures that occur simultaneously in such networks.8 cl, 2 dwg