The rising demand for automation in agriculture and manufacturing necessitates efficient, cost-effective sorting systems to replace labor-intensive manual processes. This paper introduces an innovative system integrating a Siemens S7-1200 Programmable Logic Controller (PLC), LabVIEW-based image processing, and OPC (OLE for Process Control) communication for automated tomato sorting. Utilizing real-time vision analysis, the system classifies tomatoes by color and size, offering a low-cost, scalable solution tailored for small-scale industries. A high-resolution camera captures images, processed in LabVIEW using HSV color space and size thresholds, with results relayed via OPC to the PLC, which actuates a stepper motor-driven sorting mechanism. Experimental validation in a controlled setting achieved 92% sorting accuracy and a throughput of 60 tomatoes per minute, surpassing manual sorting in speed and consistency. The modular design supports scalability to other agricultural products, enhancing its practical utility.

This paper presents a method for liquid level stabilization using a fuzzy logic algorithm implemented on the PLC S7-1200. Maintaining liquid levels accurately is a critical requirement in various industrial processes to ensure safety, efficiency, and consistent product quality. The proposed approach employs fuzzy logic to manage the inherent nonlinearities and uncertainties in the system, providing robust control performance under varying operating conditions. The fuzzy controller is designed with rules and membership functions tailored to the dynamic characteristics of the liquid level system. The control logic is programmed and deployed on the Siemens PLC S7-1200, a widely used industrial automation device. Experimental results demonstrate that the fuzzy logic controller effectively stabilizes the liquid level, achieving better performance compared to traditional PID controllers in terms of response time, overshoot, and steady-state error. This study highlights the potential of integrating fuzzy logic with PLCs for advanced industrial automation applications.

Automation or automatic control has been a growing trend in industrial fields as well as in life because of the advantages and utilities that help optimize work and reduce manpower in production. In medium and large scale automatic control systems, PLC (Programmable Logic Controller) is used as the control device for the system. In production, the transmission system using motors takes a large proportion and the problem of controlling for them to operate correctly, meeting technological requirements is one of the difficulties that need to be solved. In this study, we have applied PLC to stabilize motor speed according to preset value using PID algorithm integrated in Siemens S7–1200 PLC in order to apply research results in practice. At the limit of the article, we will present the issues of PID function block configuration, programming algorithm flowchart for PLCs, and monitoring console design for a small DC motor drive system model to verify.

Variable Frequency Drives (VFDs) are electronic power controllers that allow for accurate control of the speed of alternating current (AC) induction motors that used in many kinds of machines including fans, pumps and compressors. These motors are used in most heating, ventilation and air-conditioning (HVAC) systems and account for a significant percentage of the total HVAC energy consumption. More efficient operation of these motors using VFDs can result in significant energy savings. Besides, the communication between VFDs and PLC for Supervisory Control And Data Acquisition (SCADA) is also important. Modbus protocol has many kinds as RS485, RTU, Profinet,...In this paper we will present the communication between a PLC Siemens S7-1200 and an ATV310 Drive (Schneider) via Modbus RTU protocol which is supported.