Ladder diagram of sequential start and stop of conveyor belt Explanation: This program uses a timer (T) as the control element for delayed start and stop. The program is as follows: Component introduction: X0 is the emergency stop button X1, X2, X3 are thermal relays for three motors X4 is the start button X5 is the stop button Y1, Y2, Y3 are motor contactors Program description: 1. When the emergency stop and thermal relay are in the on state, the M0 auxiliary relay is powered on. 2. Press the start button X4 to turn on the signal, and the Y1 relay is powered on. Simultaneously connect T1 and T2. 3. When the delay time of T1 expires, the Y2 relay is powered on. 4. When the delay time of T2 expires, Y3 relay is powered on. At this point, the sequential start-up of the three electric motors is completed. 5. When the stop button X5 is pressed, the signal is...
1.1 Communication through OPC S7-200 PC Access OPC communication between S7-200 and WinCC can be established using the OPC server PC Access of S7-200. SIMATIC NET OPC Server A connection between S7-200 and WinCC can be established using the OPC server of SIMATIC NET. 1.2 Communication using PROFIBUS DP Connecting through PROFIBUS DP is a relatively fast communication method. In order to communicate using PROFIBUS DP, the S7-200 communication module EM277 is required. This document mainly provides a detailed introduction to this method. How to communicate Profibus DP between WinCC and 200PLC through EM277 2.1 Network Configuration CP5611 serves as the main station, EM277 serves as a standard master-slave network for the slave station, as shown in Figure 1. 2.2 Hardware and softwa...