• Title/Summary/Keyword: SPDS

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Proper Installation Methods of SPDs for Information-Oriented and Computerized Equipments (정보통신설비용 서지보호기의 적절한 설치방법)

  • Lee, Bok-Hee;Kang, Sung-Man;Lee, Dong-Mun;Koo, Bon-Wan
    • Proceedings of the KIEE Conference
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    • 2002.11a
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    • pp.194-196
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    • 2002
  • This paper deals with a proper installation methods of SPDs for information-oriented and computerized equipments. Since the information and computerized equipments have AC power lines and communication lines, the potential difference by lightning surge occurs between grounding points of the AC power lines and subscriber protectors, and it causes the flashover and damage. So, we have investigated the effect of the installation methods of surge protectors on the control of overvoltages, using a real-sized test circuit with a customer's facility. As a consequence, it was confirmed that the protection methods by installation of SPDs on the neighbor branch circuit was effective.

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Protection Effects Associated with Installation Conditions of SPD (SPD의 설치조건이 보호효과에 미치는 영향)

  • Lee, Bok-Hee;Lee, Dong-Moon;Jeong, Dong-Cheol;Lee, Seung-Chil
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.05a
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    • pp.298-302
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    • 2005
  • This paper presents the protection effect of SPDs according to installation conditions. To develop the effective protection countermeasures of information and communication equipments against lightning surges, actual-sized experiments in relation to the protection effects on the installation positions of surge protective devices(SPDs), the length of branch circuit the materials and long of conduit were conducted. The best method for protecting the electronic equipments from surges is to install the SPD at the front point of the devices to be protected. The installation method of the metal conduit bonded with common ground conductor were more effective than that of the PVC conduit.

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Survey of Damage Cases for Surge Protective Devices Installed Electrical Communication Systems and Analysis of Degradation Diagnosis Method (전자통신설비의 SPD 소손사례 및 열화진단기법 분석)

  • Lim, Jong-Wook;Lee, Jae-Young;Kwon, June-Hyuk
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.15-18
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    • 2009
  • In recent years electric devices and telecommunication facilities were often damaged by surge generated lightning discharge. When the service was interrupted by failure of electrical devices due to surge the social loss is very enormous. Therefore in order to protect electrical systems against lightning, SPDs(Surge protective device) have been used But damaged SPDs often make some troubles like fire and interrupt of service. In this work, 3rd harmonic leakage current defection method was applied as the diagnosis of SPD degradation and the effectiveness of this method was verified by field survey.

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A Protection Technique Against the Damages Caused by Lightning Surges on Information and Communication Facilities

  • Lee, Bok-Hee;Kang, Sung-Man;Ahn, Chang-Hwan
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.4
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    • pp.117-122
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    • 2003
  • The AC power lines and signal lines of info-communication networks are routed on overhead poles and are highly exposed to lightning strikes. Due to the potential difference between grounding points of AC power lines and signal lines, the electronic equipments connected to the signal lines can easily be damaged by lightning surges. In this work, in order to develop reliable methods of protecting information and communication facilities from lightning surges, the reliability and performance of SPDs (surge protective devices) were experimentally investigated in an actual-sized test circuit. The behaviors of SPDs against lightning surges from AC power lines and signal lines and the coordinated effects of SPD installation methods were evaluated. As a consequence, it was confirmed that the bypass arrester methods and common grounding system are both highly effective.

Application of ANOVA and DOE by Using Randomized Orders and Geometrical Properties (랜덤화 순서와 기하학적 특성을 고려한 분산분석과 실험계획의 응용방안)

  • Choe, Seong-Un
    • Proceedings of the Safety Management and Science Conference
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    • 2012.04a
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    • pp.277-292
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    • 2012
  • The research presents an application of Balanced ANOVA (BANOVA) by utilizing randomized orders for various Split-Plot Designs (SPDs) which include two cell designs, split-plot with one-way HTC (Hard to Control) factor, split-plot with two-way HTC factor, split-split-plot design and nested design. In addition, four MINITAB examples of 2-level split-plot designs based on the number of blocks and the type of whole-plots are presented for practitioners to obtain comprehensive understanding. Furthermore, the geometrical interrelated properties among three typical Designs of Experiments (DOE), such as Factorial Design (FD), Response Surface Design (RSD), and Mixture Design (MD) are discussed in this paper.

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Thermal Stability Evaluation of SPDs with Parallel or Series Circuit Assemblies (SPD 직병렬 조합회로의 열적 안정성 평가)

  • Eom, Ju-Hong;Cho, Sung-Chul
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.265-269
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    • 2005
  • Surge protective devices can be divided into three categories based on the circuit assembly: a parallel circuit type that considers the surge current amount within the device, a series circuit type that considers the voltage and single circuit type that uses a single element. However, when assembling SPDs, there are many things including function and safety to be taken into consideration because they are directly related to the performance and safety of the device. In this paper, we executed an experimental comparative study of performance and thermal stability of each SPD type using lightning surge generator and thermal image camera.

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SMART POWER DEVELOPEMEN SYSTEM FOR USE IN INTERNET (INTERNET 사용을 위한 SMART POWER DEVELOPEMENT SYSTEM)

  • Kim, Ki-Bong
    • Proceedings of the KIEE Conference
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    • 2000.11b
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    • pp.341-344
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    • 2000
  • 본 논문에서는 stepper motor 나 BLDC motor를 구동하기 위하여, 최신 microcontroller, PC, control IC board 등으로 구성된 새로운 시스템을 설명하는데 목적이 있다. 이 시스템에서는 인터넷으로 전송되는 microcontroller program를 이용하여 SPDS(smart power development system)을 구동시키고, 이로 인하여 dedicated drive IC를 제어하여 stepper 또는 BLDC motor를 구동시키게 되며, 원격지에 있는 사용자의 motor를 제어함을 목표로 하고 있다. 본 논문에서 사용된 drive IC 는 SGS-Thomson 제품으로써 stepper motor 용으로 L6205/6/7/8, 그리고 BLDC motor 용으로 L6235 이다. SPDS는 ST92F120 16-bit microcontroller를 사용하고 있다. 이 논문에서는 인터넷 Protocol Converter에 의한 프로그램 전송, Operating System Program 및 Driver Software Program의 생성 및 구성, Drive IC의 구성 및 특징, SPDS 의 hardware 및 software 의 구성 등에 대하여 설명한다.

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Effective Protection Methods of Household Electric Appliances. from Lightning Surges (가정용 전기기구의 효과적인 뇌서지 보호기법)

  • 이복희;강성만;엄주홍;이수봉;길형준;구본완;안창환
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.3
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    • pp.149-156
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    • 2004
  • This paper deals with the effective protection method for the household electric appliances against lightning surges invading from the Power lines. Direct or induced lightning is the main cause of the breakdown of household electric appliance. The most effective protection method is to install SPDs(surge protective devices) at household electric appliances. If SPDs were not installed at most household electric appliances, it is necessary to install SPDs on the mains. Therefore the propagation aspect and protection methods of lighting surges coming into household electric appliances through the mains was experimentally investigated. The in actual-sized test circuits results of protection method for 8 household electric appliances including computer monitors and TV set could be summarized as follows: The breakdown characteristics of household electric appliances from lightning surges were significantly changed with the their input impedance. Namely, the types of input impedance are classified into infinite, resistive or inductive impedances. Especially, the monitor for computer with inductive input impedance from lightning surges was relatively weak against lightning surges. It was confirmed that the self inductance of branch circuits on the mains have protection effect for household electric appliances against lightning surges invading from the power lines. Also the varistors installed at cabinet panel or circuit-breaker were more effective than multi-tap outlet with varistors. When installed varistors in cabinet panel and multi-tap outlet together, the surge protection effect is much more excellent in technical and economical aspects.

Optimal Design Method of 1-Port Surge Protective Device Based on Zinc Oxide Varistor (선화아연바리스터 기반의 1-포트 서지보호장치의 최적 설계 기법)

  • Jeong, Tae-Hoon;Kim, Young-Sung;Park, Geun-Bo;Lee, Seung-IL
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.93-102
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    • 2018
  • This paper reports a Surge Protective Device (SPD) that is used to protect an automatic metering interface (AMI) power supplies of communication equipment on a low-voltage distribution system from a lightning current. The surge protective device (SPD) can be classified as one-port SPDs and two-port SPDs with decoupling elements depending on the connection type. The protection of internal systems against the lightning current may require a systematic approach consisting of coordinated SPDs. To deal with this, the definition of a lightning protection zone (LPZ) was studied and interpreted through a theoretical review. Because the lightning current resulting from a lightning surge is considerably high, there is limited protection from one SPD; therefore, coordinated cascaded MOV-based SPDs are installed to solve this problem. Regarding the power grid mentioned in this paper, a class II SPD for the low-voltage distribution system installed on the border of LPZ1 and LPZ2, which establish a protection coordination with the Arrester (LA, SA) that corresponds to the LPZO installed on the MOF stage connected to one system were designed to protect various communication (control) equipment, including the automatic meter reading system inside the branch-type electric supply panel of a building, not the incoming side of one system. In addition, performance-related tests were done by a comparison with the existing method through testing, and the optimal design was achieved for the 1-port SPD that uses a series connection and can bleed load current without any decoupling element.

Effect of Dietary Proteins without Vitamin Premix Supplementation on the Growth and Body Composition of Juvenile Black Rockfish Sebastes schlegeli (비타민프리믹스 무첨가시 사료 중 단백질원이 조피볼락(Sebastes schlegeli) 치어의 성장과 체성분에 미치는 영향)

  • Lee, HaeYoung Moon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.2
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    • pp.146-153
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    • 2016
  • A feeding experiment was conducted to determine the nutritional value of various dietary protein sources without a vitamin premix supplementation in juvenile black rockfish, Sebastes schlegeli. Diets containing similar quantities of lipid and carbohydrate with 50% crude protein from fish meal (FM)/soybean meal (SBM)/corn gluten meal (CGM), FM only, casein/gelatin, high FM/low casein and low FM/high casein were fed to rockfish along with a commercial rockfish diet. The diet containing only 65.6% FM and the commercial rockfish diet produced significantly greater weight gain (WG) and feed efficiency (FE) than all other semipurified diets (SPDs); the economical diet with 52.8% FM, 10% SBM and 5% CGM produced lower WG than the diet containing FM and commercial rockfish diet, but FE and survival were similar both diets. Intermediate responses were observed for rockfish fed the SPD containing 32.8% FM and 27.4% casein, while SPDs containing 10% FM and 41.8% casein and 38.5% casein and 10% gelatin yielded the lowest WG and FE. Some differences in tissue indices and body composition of rockfish were induced by the diets containing various protein sources and levels without the vitamin premix supplementation.