The existing defect of overload, openphase protection of minitype flameproof motor used in coal mine was analysed and its improved protection scheme was presented.
分析了煤矿井下小型隔爆电动机过载、断相保护存在的缺陷，提出了改进的保护方案。
2
Based on the analysis of main fault types of LV (Low Voltage) flameproof motor, the negative sequence protection principle is proposed for its asymmetric short circuit fault and openphase fault.
The RPG file open can occur implicitly during the RPG initialization phase or explicitly via the RPG open operation and the use of the USROPN keyword on the file definition.