• Title/Summary/Keyword: Safety PLC

Search Result 83, Processing Time 0.033 seconds

Test of a compiler in Software Engineering Tool for Safety-grade PLC (안전등급 PLC 소프트웨어 개발도구 컴파일러 테스트)

  • Cheon, Jong-Min;Kim, Seog-Joo;Lee, Jong-Moo;Kwon, Soon-Man
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.1787-1788
    • /
    • 2008
  • 본 논문은 한국원전계측제어시스템(KNICS) 개발 사업의 일환으로 개발되는 안전등급 PLC(Programmable Logic Controller) 소프트웨어 개발 도구의 컴파일러에 대한 시험을 다룬다. 개발된 컴파일러에 대하여 외부 시스템과 연계하지 않고 내부에서 각 컴포넌트 별로 시험하는 컴포넌트 시험과 컴파일러 외부 시스템과 연계하여 시험하는 통합시험을 수행하였다. 시험 과정은 먼저 시험 계획 단계에서 시험 항목을 선정하고 각 항목 별로 사례와 시험 절차를 작성하며 이에 따라 시험을 수행한 결과를 분석하여 컴파일러의 수정 및 보완에 반영하는 것이다.

  • PDF

Design and Implementation of the Basic Technology for Solitary Senior Citizen's Lonely Death Monitor ing System using PLC

  • Huh, Jun-Ho;Seo, Kyungryong
    • Journal of Korea Multimedia Society
    • /
    • v.18 no.6
    • /
    • pp.742-752
    • /
    • 2015
  • The communications through the power lines are called as the PLC and this is a common name for the communication modes for the information delivery. This technology transmits the data through the power lines on which the information is stored with the form of high frequency signal. The characteristic of the frequency signal is that the signal can be separated from the power line through exclusive power line modem and transmitted to the terminal devices. In this paper, 'In-home Headcount' checking algorithm using Wi-Fi and taking above mentioned advantages is proposed, and the basic Technology for such Solitary Senior Citizen's Lonely Death monitoring system has been designed and implemented. The comparative analysis has been conducted in this paper with the test-operated and test bed-completed 'Hyosimi 119 Safety-Welfare System' which is still being tested since 2008. With the 'In-home Headcount Checking Algorithm', Wi-Fi connection/disconnection status and SSIDs of relevant Wi-Fis will be checked. We expect that our proposed method will become as the basic Technology which can prevent lonely deaths of elderly people living alone. Since the PLC technology can be normally implement all the functions used on internet anticipate that the technology could be applied to many areas to construct a new form of communication network.

A Programmable Electronic Systems Dedicated to Safety Related Applications (안전성이 요구되는 응용분야에 사용하는 프로그램 가능한 전자시스템)

  • Jeong, Sun-Gi;Wolfgang A. Halang;Coen Bron
    • The Transactions of the Korea Information Processing Society
    • /
    • v.1 no.4
    • /
    • pp.438-451
    • /
    • 1994
  • A low complexity, fault detecting computer architecture for utilisation in programmable logic controllers is designed. The cyclic operating mode of PLCs and a specification level, graphical programming paradigm based on the interconnection of application oriented standard software function modules are architecturally supported. Thus, by design, there is no semantic gap between the programming and machine execution levels enabling the safety licensing of application software by an extremely simple, but rigorous method, viz, diverse back translation.

  • PDF

Development of Real-time Process Management System for improving safety of Shop Floor (생산현장의 안전성 향상을 위한 실시간 공정관리 시스템 개발)

  • Lee, Seung Woo;Nam, So Jeong;Lee, Jai Kyung;Lee, Hwa Ki
    • Journal of the Korea Safety Management & Science
    • /
    • v.15 no.4
    • /
    • pp.171-178
    • /
    • 2013
  • Workers are avoiding production/manufacturing sites due to the poor working environment and concern over safety. Small and medium-sized businesses introduce new equipment to secure safety in the production site or ensure effective process management by introducing the real-time monitoring technique for existing equipment. The importance of real-time monitoring of equipment and process in the production site can also be found in the ANSI/ISA-195 model. Note, however, that most production sites still use paper-based work slip as a process management technique. Data reliability may deteriorate because information on the present condition of the production site cannot be collected/analyzed properly due to manual data writing by the worker. This paper introduces the monitoring and process management technique based on a direct facility interface to secure safety in the field by improving the poor working environment and enhance there liability and real-time characteristics of the production data. Since the data is collected from equipment in real-time directly through the SIB-based interface and PLC-based interface, problems associated with workers' manual data input are expected to be solved; safety can also be improved by enhancing workers' attention to work by minimizing workers' injuries and disruption.

Voting System Bus Protocol for a Highly-Reliable PLC with Redundant Modules (다중화 구조 고신뢰성 제어기기를 위한 보팅 시스템버스 프로토콜)

  • Jeong, Woohyuk;Park, Jaehyun
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.6
    • /
    • pp.689-694
    • /
    • 2014
  • An SPLC (Safety Programmable Logic Controller) must be designed to meet the highest safety standards, IEEE 1E, and should guarantee a level of fault-tolerance and high-reliability that ensures complete error-free operation. In order to satisfy these criteria, I/O modules, communication modules, processor modules and bus modules of the SPLC have been configured in triple or dual modular redundancy. The redundant modules receive the same data to determine the final data by the voting logic. Currently, the processor of each rx module performs the voting by deciding on the final data. It is the intent of this paper to prove the improvement on the current system, and develop a voting system for multiple data on a system bus level. The new system bus protocol is implemented based on a TCN-MVB that is a deterministic network consisting of a master-slave structure. The test result shows that the suggested system is better than the present system in view of its high utilization and improved performance of data exchange and voting.

P2HYMN: Hybrid Network Systems for Maintenance Support in Power Plants (P2HYMN: 발전소 정비지원 하이브리드 네트워크 시스템)

  • Jin, Young-Hoon;Choo, Young-Yeol
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.7
    • /
    • pp.782-787
    • /
    • 2014
  • Due to the complicated steel structure and safety concern, it is very difficult to deploy wireless networks in power plants. This paper presents a hybrid network, named as $P^2HYMN$ (Power Plant HYbrid Maintenance Network), encompassing PLC (Power Line Communication), TLC (Telephone Line Communication), and Wireless LAN. The design goal of $P^2HYMN$ is to integrate multimedia data such as design drawings of control equipment, process data, and video image data for maintenance operation in electric power plants. A Multiplex Line Communication (MLC) device was designed and implemented to integrate PLC, TLC, and Wireless LAN into $P^2HYMN$. Performance test of $P^2HYMN$ has been conducted on a testbed under various conditions. The throughput of TLC was shown as 39 Mbps. Because the bandwidth requirement per camera is 8.5 Mbps on average, TLC is expected to support more thant four video camera at the same time.

Experimental Tests on the Wireless Sensor Network and the Power-line Communication in a Real Ship and Laboratory (무선센서통신망과 전력선 통신망의 선내 및 실험실 실험결과 비교)

  • Paik, Bu-Geun;Cho, Seong-Rak;Park, Beom-Jin;Cho, In-Sung;Lee, Dong-Kon;Yun, Jong-Hwui;Bae, Byung-Dueg
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.45 no.3
    • /
    • pp.329-336
    • /
    • 2008
  • Basic performances of wireless sensor network (WSN) and power line communication (PLC) confirmed in the test bed ashore are investigated in the 3000-ton class training ship of Korea Maritime University. The ubiquitous technologies can be considered for the provision of safety and convenience in a ship. We employed WSN and PLC, as the ubiquitous technologies, at the two areas within the training ship to estimate the realization of the ubiquitous environments in a ship. The experiments show rather good results in terms of data transfer rate. However, more detailed studies concerning the connection between WSN and PLC, noises induced to power line and fading effects are required to improve the quality and the stability of the communication for the ubiquitous environments.

A Structural Testing Strategy for PLC Programs Specified by Function Block Diagram (함수 블록 다이어그램으로 명세된 PLC 프로그램에 대한 구조적 테스팅 기법)

  • Jee, Eun-Kyoung;Jeon, Seung-Jae;Cha, Sung-Deok
    • Journal of KIISE:Software and Applications
    • /
    • v.35 no.3
    • /
    • pp.149-161
    • /
    • 2008
  • As Programmable Logic Controllers(PLCs) are frequently used to implement real-time safety critical software, testing of PLC software is getting more important. We propose a structural testing technique on Function Block Diagram(FBD) which is one of the PLC programming languages. In order to test FBD networks, we define templates for function blocks including timer function blocks and propose an algorithm based on the templates to transform a unit FBD into a flowgraph. We generate test cases by applying existing testing techniques to the generated flowgraph. While the existing FBD testing technique do not consider infernal structure of FBD to generate test cases and can be applied only to FBD from which the specific intermediate model can be generated, this approach has advantages of systematic test case generation considering infernal structure of FBD and applicability to any FBD without regard to its intermediate format. Especially, the proposed method enables FBD networks including timer function blocks to be tested thoroughly. To demonstrate the effectiveness of the proposed method, we use trip logic of bistable processor of digital nuclear power plant protection systems which is being developed in Korea.

Effects of High Dose Lysophosphatidic Acid Supplement during IVC on Preimplantation Development of Porcine Embryos

  • Jin, Minghui;Yu, Il-Jeoung;Jeon, Yubyeol
    • Journal of Embryo Transfer
    • /
    • v.32 no.4
    • /
    • pp.275-285
    • /
    • 2017
  • Lysophosphatidic acid (LPA) is an important signaling molecule. Here, the effect and mechanism of LPA on the preimplantation development of porcine embryos during in vitro culture (IVC) was examined. Porcine embryos were cultured in porcine zygote medium (PZM-3) supplemented with $30{\mu}M$ LPA during different days. There was a significantly higher cleavage rate in Day 1-7 and significantly higher total cell number of blastocysts in Day 1-3 and Day 4-7. It was also found that messenger RNA (mRNA) expression level of PCNA, BCL2 and BAX in blastocysts obtained from D1-7 group were significantly higher and BCL2/BAX mRNA ratio in D1-3 group was significantly lower than control group but Day 4-7 and Day 1-7 groups were comparable with control group. Treatment with $20{\mu}M$ PLC inhibitor significantly decreased the embryo cleavage rate and blastocyst formation rate. Moreover, LPA as an activator of PLCs, enhanced the $30{\mu}M$ LPA + $20{\mu}M$ U73122 group embryo cleavage rate which similar with control group. In conclusion, the results suggest that treatment with LPA during IVC improves the porcine early embryo cleavage by activation of PLC signaling pathway and regulate the mRNA expression that contribute to total cell number of blastocysts during blastocyst formation.