OMRON小型PLC步进指令编程方法pdf,OMRON小型PLC步进指令编程方法
第1期 于宝琦等中性点不接地电力系统电容电流的补偿及测量 屯压10KV时,147.2A+6.75A(57格计算值)=点。但当单相电弧接地时,因风力、电动力、热气流的 154A 作用,使电弧拉长,往往会引起多相短路、线路跳闸或 电压95Kⅴ时,139.8A+6.7A(57格计算值)=损坏设备。因此,在中性点不接地的系统中,线路较 146.6A 长,负荷较大、单相接地电流大于自熄电流时,要设法 尽快使电流熄灭,有效措施就是在系统中性点装设消 3综述 弧线圈,合理的进行补偿 通过对系统电流的测试,正确选择消弧线圈的分 单相接地是电力系统中最常见的故障形式。系接头,使系统处于合理的补偿状态,这才能保持系统 统中性点不接地,当发生单相金属性永久接地或稳定的连续性和可幕性。 电弧接地,仍能不间断供电,这是这种电网的一大优 Compensation for and measurement of Condenser Current Neutral -point- unearthed Electric Power System YU Bao-qi; LI Hong Dept. of Automatie contrul, Beri college af Metallurgy, 117022; 2. Benxi Administration office of House property Right Berri, Lining, 117000, China) Abstract In the case of neutral- point- unearthed electric power system, earthed current depends on another two phases of condenser current when monophase ground connection takes place. If capacitance go ground is rather large, arc is not edsy to go out, thas generating overvoltage because of arc light ground connection and causing po ower cut and d equpment. Therefore, its necessary to measure the capacity of the system and use an suppressing ooil to make rational compensation so as to reinforce the reliability of power suply Key words Arc suppressing coil; Compensation mode; condenser current; Applied voltage test 护44 R5-222099 R2 9 R43J e3-四身 的99题3和和组次求出号8推出组只的计出“Rx (上接第8页) 参考文献 〔1〕李景学.可缟程控制器应用系统设计方法[M]北京:电子工业出版社,1995 2]杨长能.可編程序控制器基础及应用[M重庆:重庆大学出版社,197 Programming Method of Step Instruction in Small PLC ZHANG Jun ,LIU Zhi-jun Dept. of Automatic Control, Benci College of Metallurgy, Benxi, Liaoning, 117022, Chin) Abstract There is no individual step instruction in small PLC. This paper mtroauces a programming method of designing step program using keep instruction, and dwells on the design principle and its implementation Key words programmable logic controLler(PLC); Sequential control Step instruction