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作 者:邵昊[1] 蒋曙光[1] 王兰云[1] 梁巍巍[1]
机构地区:[1]中国矿业大学安全工程学院,江苏徐州221008
出 处:《矿山机械》2010年第8期48-51,共4页Mining & Processing Equipment
基 金:中国矿业大学煤炭资源与安全开采国家重点实验室开放研究基金资助项目(08KF13)
摘 要:目前在煤矿自动控制领域,S7-224PLC因其性能优越应用越来越广泛。但S7-224PLC没有专用的读取频率信号的模块,限制了应用的范围。利用S7-224PLC的高速计数器功能、实时时钟和MAX306多路转换器实现了对多路频率信号的读取,最大读取频率20 kHz,可以同时读取96路频率信号,信号刷新频率<1 s。S7-224PLC is widely used in the autocontrol system in colliery at present because of its superior performance. But there is no special module for reading frequency signal in S7-224PLC, which limits its application range. The present study achieves the reading of multi-channel frequency signals after it uses S7-224PLC high-speed counter's function, real-time clock and MAX306 multi-channel switch. The results show that the maximum reading frequency is 20 kHz, simultaneously reading 96 channels frequency signals has been realized and signal refresh frequency is less than ls.
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