长时间高精度定时在PLC中的实现  

Implementation of the Long Term High Precision Timing by PLC

作　　者：李渊浩[1] 崔艳芳[1] 邱培林[1] 

机构地区：[1]上海理工大学,200093

出　　处：《工业控制计算机》2005年第9期75-76,共2页Industrial Control Computer

摘　　要：常用的PLC定时方法,最大定时误差为2至3倍的扫描周期加上输入滤波器滤波时间,一般为几十毫秒。使用中断定时,可以达到毫秒级的精确度,但是由于PLC为16位寄存器,毫秒定时器只能实现几十秒定时,不能满足很多场合的要求。在此提出两种方法,解决了中断定时的时间长度问题,使PLC可以实现1ms和0.1ms精度的长时间定时。The max error of the timing method of PLC in common use is the sum of filter time and two or three times the scan loop time,the typical value is decades of milliseconds.The millisecond level definition could be reached by using the interrupt timing,but the millisecond timing can only last for decades of seconds by the restricted of the 16bit register.It can not match the need of many situations.Two techniques have been carried out to make high precision timing such as 1ms or 0.1ms lasting for a comparatively long time in this paper.

关 键 词：PLC 定时器 中断 高精度定时 长时间 毫秒级 定时方法 扫描周期 定时误差 时间长度 

分 类 号：TM571.61[电气工程—电器]