S_7-200PLC高速计数功能在拉丝计米中的应用

Application of S_7-200PLC high speed counting function to wire drawing metric calculating

滚轮式计米检测装置在拉丝计米时,由于计量滚轮磨损及其惯性转动,设备停止、启动过程中钢丝无张力等造成钢丝定长不准,给钢丝组配生产带来困难,造成材料浪费。根据拉丝机成品卷筒与驱动电机同步的原理,设计出稳定可靠的计米系统,计算出检测长度与检测量之间的关系。该计米系统由S7-200PLC,TD200文本显示器、欧姆龙增量型编码器组成,将与电机同步的编码器脉冲信号输入S7-200PLC的高速数字量输入端,利用S7-200PLC的高速计数功能实现精确计米,并给出计米检测的接线图、PLC高速计数功能的设计过程及对应的计数程序。

The roller type metric measuring device can＇t measure steel wire fixed-length correctly, cause difficulty to steel wire matching production and material wasting for measuring roller wear and inertia rotating, device stop, steel wire no ten- sion when starting and so on when wire drawing metric calculating. According to synchronous theory between wire drawing machine final capstan and drive motor, stable and reliable metric system was designed, the relationship between measuring length and measuring quantity was calculated. The system is made up of S7 -200PLC, TD200 text display, Omron incre- ment type encoder, inputs synchronous encoder pulse signal with motor to S7 -200PLC high speed digital quantity input end, uses the high speed counting function of S7 - 200PLC to realize decision metric counting. The wiring diagram of metric measuring, designing process of PLC high speed counting function and corresponding counting procedure were given.