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关键词： 交流接触器   可靠性研究   电寿命  

摘要： 基于相关的文献和标准,对交流接触器可靠性进行了研究。分析并研究了交流接触器可靠性指标体系、可靠性试验方法和装置,最后对交流接触器可靠性技术研究进行了展望。该项研究对工业生产的安全运行和振兴民族电器行业有着重要意义。

关键词： 智能接触器   数据采集   霍尔传感器  

摘要： 随着电力网及其他控制系统和保护电路对交流接触器性能要求的日益提高,希望设计制造出体积小、重量轻、寿命高、精度和可靠性高、节能、可通信、价格合理的交流接触器。本课题的研究具重要的经济意义和社会应用价值。主要介绍霍尔传感器在智能接触器数据采集中的研究应用。

关键词： .mitigation   stress analysis   lamina   SMA wires   composite plate   post-buckling   alloy hybrid   Local buckling   ECTE   SMA material   SMAHC layer   SMAHC plates   central cutout  

摘要： In this study, the numerical model of a shape memory alloy hybrid composite (SMAHC) plate was constructed. The model was based on the effective coefficient of thermal expansion (ECTE) model of the shape memory alloy (SMA) material. The embedded SMA wires were modeled as an integrated composite layer in conjunction with the host composite lamina. The tailored design feature of laminated composite plates allows the flexibility of orienting the SMAHC layer along different directions. The response of the SMAHC plates with and without a central cutout, having certain geometric imperfections, subjected to an initial in-plane compressive loading and a subsequent elevated thermal load, were investigated numerically and experimentally. It was established that the positive attribute of the SMA material could be used to successfully suppress the post-buckling deflection of the SMAHC plate under an elevated temperature, when the SMA wires were properly oriented. The variation of stress concentration around the cutout of the SMAHC plate was also investigated. It was found from this study that the orientation of SMA wires had a significant influence on the suppression of the lateral deflection. The extent of such a positive attribute was found to be influenced by the boundary condition of the SMAHC plate.

摘要： Drawing on theory and empirical findings from a 35-year research program in the behavioral sciences on how to improve professional effectiveness through reflective practice, we develop a model of "debriefing with good judgment." The model specifies a rigorous reflection process that helps trainees surface and resolve pressing clinical and behavioral dilemmas raised by the simulation. Based on the authors' own experience using this approach in approximately 2000 debriefings, it was found that the "debriefing with good judgment" approach often sparks self-reflection and behavior change in trainees. © 2007 Elsevier Inc. All rights reserved.

关键词： 空调系统   运算器   锅炉   循环   结构细节   计数器   浸没深度   设计   尺寸规格   电端子   能量   供能系统(建筑物)   流量计   流动   熔断器   热学   耗热量表   热交换器   传热介质   加热设备   加热技术   热量测量仪表   铭刻   接口   接口(数据处理)   液体   低电压   作标记   材料   测量   机械接口   介质   动量   热质量   安全性   安全装置   传感器   规范(验收)   温度   热环境系统   温度探头   类型  

标准号: BS EN 1434-2-2007

摘要： This European Standard specifies the constructional requirements and applies to heat meters, that is to instruments intended for measuring the heat which, in a heat-exchange circuit, is absorbed (cooling) or given up (heating) by a liquid called the heat-conveying liquid. The heat meter indicates the quantity of heat in *** safety requirements are not covered by this European *** safety requirements are not covered by this European *** mounted temperature sensors are not covered by this European Standard.

关键词： 空调系统   认可测试   循环   交付使用   计数器   定义   设计   电气设备   能量   熔断器   热   耗热量表   热交换器   传热介质   加热器   加热工程   加热设备   安装   仪器   维修   测量   测量仪器   监测   安装条件   过电压保护   质量   热量   安全装置   规范(验收)   监督(认可)   温度   测试   热的   热环境系统   温度探头  

标准号: BS EN 1434-6-2007

摘要： This European Standard specifies installation, commissioning, operational monitoring and maintenance and applies to heat meters, that is to instruments intended for measuring the heat which, in a heat-exchange circuit, is absorbed (cooling) or given up (heating) by a liquid called the heat-conveying liquid. The heat meterindicates the quantity of heat in legal *** safety requirements are not covered by this European *** safety requirements are not covered by this European *** mounted temperature sensors are not covered by this European Standard.

关键词： 交流电流   接触器   控制装置   电控制器   技术要求  

标准号: JB/T 8591.2-2007

摘要： JB/T 8591的本部分规定了CJ26、CJ28系列交流接触器的基本要求,包括术语、特性、正常工作和安装条件、结构和性能要求、试验项目及试验方法等。接触器主要用于交流50Hz(或60Hz)、额定电压至660V,电流为CJ26系列接触器至32A、CJ28系列接触器至475A的电力系统中接通和分断电路,并与适当的热继电器或电子保护器组合成电动机起动器,以保护可能发生过载的电路。

关键词： 低压电器   接触器   转动式接触器   交流接触器  

标准号: JB/T 8980-2007

摘要： 本标准规定了转动式交流接触器(以下简称接触器)的基本规则和要求,包括术语、特性、正常工作和安装条件、结构和性能要求、验证特性和性能要求的试验方法与规则和标志等。本标准适用于交流50Hz,额定电压至交流1000V电力线路中的接触器,主要供冶金、轧钢企业起重机等的电气设备中,作远距离接通和分断电路,并作为交流电动机频繁的起动、停止和反接等之用。

关键词： 低压交流接触器   额定电压   电磁线圈   选用原则   电压等级   负载  

摘要： 1 交流接触器的选用原则 1．1 电压的选择。接触器的电磁线圈额定电压有36，110．220，380V等，电磁线圈允许在额定电压的85％～110％范围内使用。接触器的额定电压要大于或等于负载的额定电压。交流接触器的电压等级要和负载相同，选用的接触器类型要和负载相适应。

关键词： 高压熔断器   结构改进   插入式   户外   交流电力系统   过电流保护   结构示意图   短路保护  

摘要： 插入式户外高压熔断器，适于10kV交流电力系统中作配电线路和变压器的短路保护与过电流保护。它是一种顶盖密封、抗雨雪、抗污秽能力强、内插式结构、双点灭弧的保护装置。结构示意图如图1所示。