Improving Efficiency of Safety Cut-Out of Mining Machines
B. B. UTEGULOV, A. B. UTEGULOV, A. B. YAKHITOVA
Seifullin Kazakh AgroTechnical University, pr. Pobedy 62, Astana, 010000, Kazakhstan
Keywords: горные предприятия, экскаватор, устройство защитного отключения, электробезопасность, состояние изоляции, mines, shovel, safety cut-out, electrical safety, electrical insulation condition
Abstract
Electrical insulation of open pit shovels has been tested. It is found that line-to-ground short circuit current in up to 1000 V network is lower than setting current of safety cut-out. The authors propose a method to improve efficiency of safety cut-out of mining shovels and drill rigs. The method is based on superimposing D/C current on three-phase network with fixed setting of cut-out operation, i.e. when a person touches live parts the electrics is cut-out owing to increase in capacitance of phase relative to ground.
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