%ARittinghaus, D
%D1981
%I;
%JETZ Arch.; (Germany, Federal Republic of)
%K42 ENGINEERING, 01 COAL, LIGNITE, AND PEAT, ELECTRIC IMPEDANCE, ELECTRICAL FAULTS, ELECTRIC IMPEDANC, CALCULATION METHODS, MEASURING INSTRUMENTS, UNDERGROUND MINING, ELECTRICAL EQUIPMENT, ELECTRIC CURRENTS, CURRENTS, EQUIPMENT, IMPEDANCE, MINING, 422000* - Engineering- Mining & Underground Engineering- (1980-), 012000 - Coal, Lignite, & Peat- Mining
%PMedium: X; Size: Pages: 319-323
%TMeasurements of impedances for determinating the minimum short-circuit current in main systems 500 V of underground mining establishments
%XThe complex short-circuit impedances of energized low-voltage main systems were measured with a double-bridge in underground mining operation. The magnitude of the short-circuit currents depends on these impedances. Customary calculations of such currents depend on empirical approximations. To verify the accuracy of these approximations, the measured impedances of 61 nodes in three different main systems were compared with the results of the calculations. The comparison made between the short-circuit currents determined by measurable quantities and the values calculated according to VDE 0118 shows that the stipulated coefficients for calculating the minimum short-circuit currents lie very far on the safe side. An amendment for calculating the short-circuit in accordance with VDE 0118 is therefore suggested.
%0Journal Article
Germany Journal ID: CODEN: ETZAD DE German