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1、 对漏电保护器的安全性能剖析摘要： 在现行建筑行业为了用电安全常使用漏电保护器。 本文着重阐述了漏电保护器的重要作用、工作原理、使用范围及注意事项，同时也指出了今后建筑电气安全保护方面的发展趋势。 关键词： 漏电电流 碰壳短路 相地短路 随着改革开放不断深入发展，人民的生活水平也在不断地提高。 如电冰箱、洗衣机、电视机、空调、电饭煲、微波炉多种多样的电气设备越来越多地进入千家万户，被众多居民普遍使用。 这些众多的家用电器，对于保护人身与设备的安全意识，引起了国内外人士的广泛关注。 因此，对建筑电气的设计和施工也提出了更高的要求。 当前，在中性点直接接地的380/ 220V 的低压配电
2、系统中，已经开始采取将质量合格参数合格的漏电保护器与接地保护或接零保护正确地配合使用，较好地防止了漏电电击等事故的发生。1 漏电保护器安装的必要性保护接零一般采用TN-C-S 系统或TN-S 系统，也就是在电源入户之前将零线重复接地，且重复接地电阻10。 而在进户之后，工作零线N 与保护零线PE 则须分开。 此时，PE 线与所有用电设备金属外壳通过三孔插座的接地孔连接起来。而零线在引入配电箱后，应当和相线一样对地绝缘。 如果发生相线碰壳短路情况时，短路电流则经零线和接地极构成闭合回路。 这时回路阻抗很小，短路电流很大，从而此较大的短路电流致使保护开关跳闸，切断电源回路，达到安全保护的目的。 如
3、图1 所示。 短路电流IK = U/Zd式中： IK相线碰壳短路电流，AU 相电压，Zd 零线阻抗与重复接地电阻之和，但是，TN-C-S 系统只能对用电设备的外壳在带电时起到保护作用，而对相地短路的情况则不能起到保护作用。 其原因是：在相地短路时(即设备绝缘破损发生的单相对地短路，简称故障短路) ，短路电流要经过设备与地面的自然接触，电阻流向电源中性点。 由于这时自然接触电阻很大，而短路电流很小，不足以使熔断器、断路器动作，切断电路，却能使故障引发的电弧火花持续很长时间，甚至着火。 如图2 所示。 为了克服以上存在问题，在建筑电气设计、施工中采用安装漏电保护器，就成为一种有效的触电或漏电保护手
4、段。另外，在居民住宅中安装漏电保护器，也是当今我国按照国标GB6829295 标准要求，进行设计与施工的需要。2 漏电保护器的工作原理漏电保护器是由零序电流互感器、漏电脱扣器、脱扣机构、主开关、实验按钮等五部分组成。 倘若发生被保护设备的接地故障电流作用于漏电保护器的漏电脱扣器上的情况，其电流超过预定值时，则会立即出现开关跳闸，从而切断了故障电路。 如图3 所示。 一般来说在正常情况下，各相电流的相量和等于零。 由此，各相电流在零序电流互感器铁芯中感应的磁通量之和也等于零。 这时，由于零序电流互感器的二次侧绕组无信号输出，主开关仍处于闭合状态，电源继续向负载方向供电。当发生接地故障，或设备绝缘
5、损坏、漏电，或人触及带电体时，主回路中各相电流的相量和不再为零。 则会出现故障电流在零序电流互感器的环形铁芯中产生磁通，从而导致二次侧感应电压迫使脱扣线圈励磁，强令主开关跳闸，切断供电回路。由上可知，电流型漏电保护器是基于基尔霍夫第一定律：流入电路中任一节点的复电流代数和等于零，即I = 0。 3 漏电保护器的作用及使用范围漏电保护器具有动作灵敏，切断时间迅速的性能。 在建筑电气设计施工中只要合理选用和正确安装，对保护人身安全和防止设备损坏，以及预防火焰将会有明显的作用。(1) 当人体直接触及220V 带电体时，漏电保护器迅速以0.1 秒的时间快速切断电路。 这时流过人体(一般人体电阻为1 0
6、00左右) 的触电电流为220/ 1 000 = 220 (mA) ，其电击能量为：220(mA) 0. 1 (S) = 22mAS < 30mAS。 目前我国现行规定：对人体安全的电击能量为：1T = 30mAS ，可以明显看出，当人们一旦触及220V 带电体时，漏电保护器会在0. 1 秒时间内迅速作出反应，而不致出现生命危险。(2) 在TN-C-S 或TN-S 系统中，未装漏电保护器时，如果发生接地故障情况，设备外壳会产生对人身有危险的接触电压；当装有漏电保护器之后，即使发生了接地故障，接触电压在还没有达到危及人身生命时，漏电保护器就会立即切断电源回路。 其理由是：在住宅建筑电气设计
7、时，设计者已为用户所安装的漏电保护器选择了额定动作电流小于或等于30mA ，动作时间为0. 1 秒。 当发生接地故障时，只要有漏电电流产生，就会在漏电电流小于或等于30mA 时，漏电保护器就立刻动作，切断了电源回路。 同时，30mA 的电流在0. 1 秒时间内作用于人体不会危及生命安全。(3) 安装漏电保护器对配电线路的绝缘水平起到监察作用。 如果设备出现碰壳故障或绝缘损坏，就会有漏电电流产生。 当漏电电流达到漏电保护器的额定动作电流时，将立即动作切断电源回路。 也就是说，在人尚未触及故障设备危险的接触电压之前，就已经将故障线路切断了。 从而提前避免了触电死亡及火灾事故的发生。(4) 一旦出现
8、发生接地故障时，由于切断故障线路因素不是依靠过电流保护，而是依靠漏电保护。 再则，漏电保护的额定动作电流数值很小，与过电流相比，相差1000倍10000倍。因此，出现在设备外壳的接触电压也很低，一般小于50V ，大大提高了安全性。4 漏电保护器使用时应注意事项(1) 漏电保护器适用于电源中性点直接接地或经过电阻、电抗接地的低压配电系统。 对于电源中性点不接地的系统，则不宜采用漏电保护器。 因为后者不能构成泄漏电气回路，即使发生了接地故障，产生了大于或等于漏电保护器的额定动作电流，该保护器也不能及时动作切断电源回路；或者依靠人体接能故障点去构成泄漏电气回路，促使漏电保护器动作，切断电源回路。 但
9、是，这对人体仍不安全。 显而易见，必须具备接地装置的条件，电气设备发生漏电时，且漏电电流达到动作电流时，就能在0.1 秒内立即跳闸，切断了电源主回路。(2) 漏电保护器保护线路的工作中性线N 要通过零序电流互感器。 否则，在接通后，就会有一个不平衡电流使漏电保护器产生误动作。(3) 接零保护线(PE) 不准通过零序电流互感器。 因为保护线路(PE) 通过零序电流互感器时，漏电电流经PE 保护线又回穿过零序电流互感器，导致电流抵消，而互感器上检测不出漏电电流值。 在出现故障时，造成漏电保护器不动作，起不到保护作用。(4) 控制回路的工作中性线不能进行重复接地。 一方面，重复接地时，在正常工作情况
10、下，工作电流的一部分经由重复接地1回到电源中性点，在电流互感器中会出现不平衡电流。 当不平衡电流达到一定值时，漏电保护器便产生误动作；另一方面，因故障漏电时，保护线上的漏电电流也可能穿过电流互感器的个性线回到电源中性点，抵消了互感器的漏电电流，而使保护器拒绝动作。(5) 漏电保护器后面的工作中性线N 与保护线(PE) 不能合并为一体。 如果二者合并为一体时，当出现漏电故障或人体触电时，漏电电流经由电流互感器回流，结果又雷同于情况(3) ，造成漏电保护器拒绝动作。(6) 被保护的用电设备与漏电保护器之间的各线互相不能碰接。 如果出现线间相碰或零线间相交接，会立刻破坏了零序平衡电流值，而引起漏电保
11、护器误动作；另外，被保护的用电设备只能并联安装在漏电保护器之后，接线保证正确，也不许将用电设备接在实验按钮的接线处。以上叙述的几条注意事项，都是很容易在使用中出现错误的地方，故在本文中特地提出来，希望读者在使用漏电保护器时格外注意。5 结论漏电保护器的使用对低压供电系统的安全可靠性起到了很重要的作用，它弥补了IN-C-S 与IN-S 系统的不足。 但是，还不能说用了漏电保护器，在供电系统中就万无一失了。它并不是防止电击事故的惟一措施，也不是特效措施。 譬如，在高层建筑中，往往把高低压配电室的电气设备金属外壳、金属板、建筑物钢筋基础网连接起来。 如果高压电气设备外壳碰壳带电，便会产生一个120V
12、 的危险电压(10KV 对地电容电流为30A ，接地电阻4 ，30 4 = 120 (V) ) ，该电压通过PE 线窜到低压设备的外壳，漏电保护器对PE 线无法检测，造成保护失效。 欲要克服这种不足，则应通过实施用国际电工委员会的标准及GB50054-95 规范中推行的等电位联结的方法去解决。参考文献1 凌智敏.剩余电流保护器讲座J . 电世界，1996 (10) .2 周鸿昌1 配电系统的安全用电与漏电保护J . 建筑电气.1993（1）./Porganization system and working mode, the selection of a number of municipa
13、l strengthening group to build innovation and strengthen the organization of the basic level organizations advanced model.(seven) the manual work of the Communist Youth League Organization published and League branch of manual work, to promote the use of two manuals in the citys organizations at var
14、ious levels. The county committee, directly under the group (work) is under the jurisdiction of grassroots League and group (total) using branch ratio shall not be less than 70%.Three, to further strengthen the groups leadership and team building(a) to strengthen the leagues leadership at all levels
15、 of construction. Continue to do a good job of municipal Party Committee Organization Department on the strengthening of the Communist Youth League cadres management opinions implementation. To promote the group counties (autonomous counties, cities) Commission and city directly under the group (wor
16、kers) appointed to carry out the Five team building activities. Improve the League Association Department working mechanism. Conscientiously fulfill the duties of CO, combined with the city group directly under (the) Committee of the general election and the adjustment, actively jointly with the uni
17、t where the party organization department good group leadership selection with the work. Do a good job in municipal Party committee assistant committee leadership and leading cadres of the annual assessment work, adhere to and improve the assistant secretary of the Communist Youth League talk system
18、 group To weave individual conversation and collective conversation, to strengthen the committees of all levels, the Standing Committee of the Standing Committee, the establishment of a sound system of central group learning, the system of investigation and study, the system of important issues and
19、the reporting system.(two) to strengthen the work of education and training of cadres to conscientiously implement the Central Committee. On the implementation of grassroots cadres training project and opinions on carrying out the mission municipal CYL Cadres training project implementation opinions
20、, full implementation of the project of the City Youth League cadres training education. Focus on the county grassroots cadres and workers focused on training, the new school system vocational training League cadres, for the Municipal Organization Department jointly held the third session of the Com
21、munist Youth League system training cadres in party. Focusing on the construction of new socialist countryside, strengthening village cadres and rural construction team group member of the young team, the county organizations at various levels throughout the year is expected to train 100 00 rural gr
22、assroots cadres, plans to train 1000 village secretary of the village Party branch.(three) actively promote grassroots cadres election work. Under the unified leadership of the party organization, to strengthen grassroots organizations direct work, standardize the election work rules and procedures,
23、 in the designated candidate, open competition to democratically elected branch secretary at the same time, actively and steadily the development of Township, streets and other grassroots organizations in the direct election of the pilot work, on the basis of summarizing the experience and gradually
24、 expand the scope of the pilot, and gradually formed a set of measures and cadres election system.(four) to strengthen the cadres testing exercise. To study the development of XX city from 2006 to 2008 cadres testing exercise planning. To select outstanding cadres to the central mission in Beijing,
25、Shanghai, Guangzhou and other central organs and sending work in developed areas. With the Central Committee the implementation of the western region and ethnic minorities cadres training plan . To carry out the eighth batch of municipal organs attachment cadre management, selection, training work.
26、The outstanding cadres to start the National Development Bank XX branch testing exercise.(five) to strengthen the group construction. The main position to play the role of Youth League cadre education and training as the city, in accordance with the requirements of post training, further curriculum
27、scientifically and rationally, adopt arrangement menu course, basic theory includes group work, focus, hot and difficult issues, to enhance the content and practice; to strengthen the construction of teaching staff, the integration of teachers, establish a quality teacher training team, establish an
28、d implement course evaluation system; take delivery of training to the countryside, on-site training, and increase the rural grassroots cadres training efforts.Four, efforts to strengthen the work of young talent(a) to tenth XX young 54 medal in recognition of the publicity, and actively explore the
29、 XX youth service. 54 Medal of institutionalization, standardization and socialization mechanism. Give full play to the XX award in recognition of 54 youth medal Association, Youth Award winner in the 54 chapter, investigation activities. Who won the Youth Service medal, dedication to the society to
30、 create conditions, build the stage. During the 54, named in recognition of the tenth XX young 54 medal. The association of XX editing of young talent , the exchange of information and communication platform for the XX of outstanding young talents.(two) the establishment of municipal Party committee
31、 of young talent information database. In accordance with the feasible, effective, classification management, implement step by step principle, the establishment of municipal Party committee of youth talent database; guiding organizations at various levels generally established the young talent data
32、base, construction of city, county (directly under the Communist Youth League), grassroots organizations three young talent information database the relevant information collection system, and gradually establish the citys young people, the Communist Youth League youth talent information network, pr
33、ovide information platform for young talent resource development.Five, take effective measures to strengthen the mission management(a) to strengthen the mission management work. Strengthen the dues collection and management, continue to adhere to the dues collection regularly reporting system, the a
34、nnual comprehensive award in recognition of the tour and the tour one vote veto system audit system. Do statistical work in the group. The group service award in recognition of the advanced units, standardization, promoting group management work institutionalized.(two) to strengthen the organization
35、 of research and information exchange efforts. Grassroots carry out research, efforts to form a number of theoretical results. Make full use of the network carrier, to explore the establishment of electronic group service system, promote the work of Communist Youth League information.Attachment 4:XX
36、 municipal Party Committee Propaganda Department of the Communist Youth League work pointsIn 2006, the Communist Youth League propaganda ideological work XX to Deng Xiaoping theory and the important thought of Three Represents as guidance, study and implement the partys sixteen and the spirit of the
37、 the fifth Plenary Session of the 16th CPC Central Committee implementation of the eight plenary session of the two committee, the citys cultural work conference, the Propaganda Department of the meeting and the the fourth Plenary Session of the 15th CPC Central Committee permanent mission spirit, c
38、losely around 11th Five-Year XX the goal of full implementation of Scientific Outlook on Development, emancipating the mind, seeking truth from facts, keep pace with the times, close to reality, close to life, close to the young, persevere grasp orientation, grasping deepening, grasping construction
39、 innovation, further improve the groups propaganda and ideological work ability, unity To guide the majority of members of the youth to achieve the 11th Five-Year planning tasks, the overall construction of a well-off society, building a socialist harmonious society to make new contributions.One, ad
40、here to the Three Represents important thought and Scientific Outlook on Development education to guide the youth, to further strengthen the ideological and political education of youth(a) armed with youth science theory. Unremittingly with Deng Xiaoping theory and the important thought of Three Rep
41、resents armed members of youth education, to promote the study and implement to expand the depth and breadth. To study and implement the important thought of Three Represents with the establishment and implementation of Scientific Outlook on Development combine with the implementation of the require
42、ments of constructing socialist harmonious society with Scientific Outlook on Development, carry out education as an important part of the theory of armed youth in the new period, strengthen the establishment and implementation of Scientific Outlook on Development education, educate and guide the yo
43、uth to fully understand the great significance of establishment and implementation of Scientific Outlook on Development, in-depth understanding of the Scientific Outlook on Development era back The king, the practice foundation, basic connotation, historical status, spirit and practice requirements,
44、 a profound understanding of Scientific Outlook on Development with Marxism Leninism, Mao Zedong thought, inheriting and developing relationship between Deng Xiaoping theory and the important thought of Three Represents, to help young people establish and consciously practice Scientific Outlook on D
45、evelopment. Persist in learning, grasping the backbone, grasp the practice, grasp the opportunity. Catch club, effective way to grasp the network, with the group of cadres, young students and young backbone fronts as the focus, to promote the work of the armed youth theory to develop in depth, to he
46、lp the youth continue to firm ideals and beliefs, to build a powerful spiritual pillar. To carry out the study and implementation of the partys sixteen session of the five Eight plenary session of the two plenary session of the Central Committee and the party spirit, to the citys Youth League member
47、s thinking into the spirit of the meeting, to achieve the goal of national consciousness and XX economic and social development in 11th Five-Year period. Contribute to help and guide the youth to a profound understanding of the significance and main task of building a socialist harmonious society, a
48、ctively join the construction of socialist harmonious society.(two) to strengthen the ideological and moral construction of teenagers. Thoroughly implement the central spirit of the document No. 8, No. 16 and the program for Improving Civic Morality to minors and students as focus groups, to strengthen and improve the ideological and moral construction of minors and the ideological and political education of college students. Make full use of the spirit and the spirit of the Three Gorges migrants Hongyan XX unique the use of educational resources, scho
