• Journal of the Korean Society for Precision Engineering
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• v.20 no.10
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• pp.89-97
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• 2003

The faults diagnosis of machine tool, which is controlled by CNC(Computer Numerical Control) and PLC(Programmable Logic Controller), is generally based on ladder diagram of PLC because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching of logical relationship for fault reasons is required a lot of diagnosis experiences and times because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault fast and correctly. The diagnosed reasons for fault are remote serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2811-2813
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• 2000

Nowadays PLC is used for controlling various industrial processes. For its better performance operating status of PLC should be continuously checked. However. it is difficult to monitor the status of PLC owing to the spatial limitation. This paper presents an internet based remote monitoring and control system for PLC and a practical implementation for Tiny PLC is executed for verifying its feasibility.

• Journal of Advanced Navigation Technology
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• v.14 no.6
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• pp.824-830
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• 2010

PLC_Zigbee system, implemented in a previous study, uses ZigBee Node based on PLC (Power Line Communication). The weak point of the system is that the long distance powerline communication and PLC is impossible to use in the areas where the powerline is not installed. In this paper, we added CDMA (Code Division Multiple Access) module using a data transfer method of SMS (Short Message Service) and XBee of WSN (Wireless Sensor Network) module to the previous system, and got around the restriction of place and environment of PLC system through the interfacing of each communication media. We, thus, implemented a wide range of real monitoring system.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.271-278
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• 2017

This paper introduces a user-friendly PLC (programmable logic controller) monitoring and control system of heavy machinery using Android based smartphone. The proposed system will control diesel generator and many such like machine without a dedicated PC with respect to similar system and offers a new communication protocol for handling it. The smartphone controls the generator via Wi-Fi, through which it connects to the Raspberry pi which will be installed in the PLC panel to setup the communication between them. Furthermore, Raspberry pi connects to two devices, one is PLC which gives the status and current information of the machine and to ON/OFF the machine. This proposed system used RS485 as a key mediator for data exchanging between Raspberry PI(master) and PLC(slave). RS485 allows multiple devices (up to 32) to communicate at half duplex on single pair of wires and provides a long connectivity area (up to 1200 meters) as compared to another device. This proposed system specially focused on accurate data flow between smartphone and PLC panel.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.1
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• pp.51-57
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• 1999

This thesis is written about the Wired Logic Type Unit in developing equipment that the load is driven, that the interface unit connect with 1 Scan time to PO30 of operated PLC output contact with that a sensing signal of Temperature Sensor RSD Pt $100\Omega$ let generate the relay output of temperature controller and input the PLC. The PLC Test Kit in country that the PLC to be programmed at the PLC education place is able to drive the load, is done to do a education of PLC on status that interface process between PLC and load are disregarded. As Developing Kit for supplement this point, when the relay output of temperature controller to use Pt 100 of temperature sensor as mentioned on the former among every kinds of sensor feed back to the input of the PLC, as the equipment to act with real time system that the output contact of PLC operated to insert the WLTIJ among PC, PLC and the load, it can understand and see very easy the main principle of PLC use. The structure of WLTU to be a interface unit of load separated as to the point of contact and noncontact, sensor, indicating lamp and A contact and B contact that is belong to driving part, and a motor is belong to loading part.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.17-23
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• 2020

In this paper, collecting real-time data frames that occur during RS232 communication between an HMI and PLC of automation equipment by sniffing real-time information data frames through MCU without modification of the HMI or PLC, a method is proposed that allows users to collect data without being dependent on the modification of PLC and HMI systems. The user collects necessary information from the sniffing data through the parsing operation, and the original communication interface is maintained by transmitting the corresponding sniffing frame to the destination. The MCU's UART communication interface circuit is physically designed according to the RS232 communication standard, and this additionally improves efficiency more so than an interrupt-based system by using the DMA device inside the MCU. In addition, the data frame IO operation is performed by logically separating the work of the DMA interrupt service routine from the work of the main thread using the circular queue. Through this method, the user receives the sniffing data frame between the HMI and PLC in RS232 format, and the frame transfer between PLC and HMI arrives normally at the original destination. By sniffing the data frame without further modification of the PLC and HMI, it can be confirmed that it arrives at the user system normally.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.11a
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• pp.31-34
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• 2006

최근의 PLC는 Ethernet 통신, Field Bus등 새로운 통신규약에 호환성을 갖고 있으며 점점 빠른 연산 속도의 초소형 PLC로 발전해 나가고 있고 공장 자동화와 FMS(Flexible Manufacturing System)에 따른 PLC의 요구는 과거 중규모 이상의 릴레이 제어반 대체 효과에서 현재 고기능화, 고속화의 추세로 소규모 정작 기계에서 대규모 시스템 설비에 이르기까지 적용되고 있다. 그러나 현재 사용되고 있는 PLC는 각 제조사마다 하드웨어형식은 유사하지만 소프트웨어형식인 제어 명령어들이 다르기 때문에 각각의 PLC마다 호환이 되지 않는다는 문제점을 가지고 있어 이 제어 명령어들의 호환성을 위한 솔루션이 필요하다. 이를 해결하기 위하여 본 논문은 IEC1131-3의 표준 언어를 중심으로 제어할 수 있는 Mo-aPLC라는 모바일 에이전트 기반의 softPLC시스템을 제안하였다. 이 시스템은 모바일 에이전트들이 지적 대리인으로서 IEC1131-3의 표준 언어를 제어시스템 제작자에게 활용되어 질 수 있는 코드인 IL언어로 변환하고 이를 랭귀지 프로그래머가 활용할 수 있는 코드인 표준 C코드로 변환하는 것이다. 이 시스템으로 인해 제어시스템 제작자와 랭귀지 프로그래머들이 활용할 수 있는 코드들이 생성되는 것과 표준 C코드로 변환함으로서 논리적인 디버깅(dubugging)이 용이하다는 것을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.617-622
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• 2018

In industries such as automobiles and semiconductors, a lot of components are produced using PLCs based on an automatic production system. Therefore, an educational platform is needed to provide training in the use of PLCs in the industrial sites. Conventional educational systems, in which PLCs are employed to control sensors and actuators, have been continuously developed. However, these systems present their circuits only in 2D on the screen, which makes it difficult to understand them during the learning process. To overcome these disadvantages, we propose an educational V-Factory system capable of providing PLC training using virtual reality. In addition, thousands of sensors and actuators can be controlled by the V-Factory system through the proposed virtual I/O driver. The motion of the automatic production system can be visualized using virtual reality.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.7-10
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• 2002

The diagnosis of faults of machine tool, which is controlled by CNC and PLC, is generally based on ladder diagram of PLC. Because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching for logical relation to fault reasons is required a lot of fault experiences and times, because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault lastly and correctly. The diagnosed reasons for fault are tele-serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.127-136
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• 2019

The public address system should be easily operated and managed by the users, and guaranteed to serve stable working in an emergency and a crisis. In this paper, In this paper, to provide power line communication based public address system users with convenience and efficiency, we implement a firmware to control communication between a PLC(: Power Line Communication) controller of the public address system and UI(: User Interface) and between a PLC controller of the public address system and PLC speakers, and develop a UI software.