PLC 控制电机正反转段庆安[摘 要]：可编程控制器（PLC）是以微处理器为核心，将自动控制技术、计算机技术和通信技术融为一体而进展起来的崭新的工业自动控制装置.目前 PLC 已基本替代了传统的继电器控制而广泛应用于工业控制的各个领域，PLC 已跃居工业自动化三大支柱的首位。生产机械往往要求运动部件可以实现正反两个方向的起动，这就要求拖动电动机能作正、反向旋转.由电机原理可知，改变电动机三相电源的相序，就能改变电动机的转向。按下正转启动按钮 SB1,电动机正转运行,且 KM1，KMY 接通.2s 后 KMY 断开，KM 接通，即完成正转启动。按下停止按钮 SB2，电动机停止运行。按下反转启动按钮 SB3，电动机反转运行，且 KM2,KMY 接通。2s 后 KMY 断开，KM 接通，即完成反转启动。[关键词]：PLC 直流电机PLC control motor reversingDuan Qing an[Abstract]: Programmable Logic Controller （ PLC ） is a microprocessor core ， automatic control technology, computer technology and communication technology integration and the development of a new industrial automatic control device. PLC has basically replaced the traditional relay control is widely used in various areas of industrial control, PLC has leapt to the first of the three pillars of the industrial automation。Production machinery often require moving parts can be achieved in both directions of the starter, which requires the drag motor can make positive and reverse rotation。 Seen by the motor principle, change the phase sequence of the motor three-phase power， will be able to change the direction of the motor rotation. Press Forward Start button SB1 motor forward run and KM1 KMY turned on。 2s after and KMY disconnect, KM switched to complete the forward start 。 Press the stop button SB2， the motor stops running。 Press the start button reversal SB3 motor reverses and KM2 ， the KMY switched 。 2s after and KMY disconnect ， KM switched complete reversal to start.[Keyword...
