摘要：隨著我國(guó)經(jīng)濟(jì)發(fā)展速度的進(jìn)一步加速，人們的生活水平也得到了不斷地提升，不斷加大居民的用電量，各種家用電器方便了人們生活的同時(shí)，在一定程度上對(duì)居民的生活也產(chǎn)生了較大的隱患。在建筑電氣工程中，若有漏電問(wèn)題的發(fā)生，就會(huì)影響著人們的日常生活，還會(huì)威脅著人們的生命**。因此，需要采用漏電保護(hù)技術(shù)，在電氣工程系統(tǒng)中加入漏電保護(hù)裝置，從容合理地降低施工人員的觸電幾率。

關(guān)鍵詞：漏電；施工；觸電

Abstract: With the further acceleration of my country’s economic development, people’s living standards have also been continuously improved, and residents’ electricity consumption has been continuously increased. While various household appliances have made people’s lives more convenient, they also provide a certain degree of benefit to residents. Life has also produced greater hidden dangers. In building electrical engineering, if there is a leakage problem, it will affect people's daily life and threaten people's lives. Therefore, it is necessary to adopt leakage protection technology and add leakage protection devices to the electrical engineering system to calmly and effectively reduce the chance of electric shock for construction workers.

Keywords: electric leakage; construction; electric shock

0：概述General

   對(duì)于建筑電氣的施工，能夠引起電氣施工不**的因素很多，歸納起來(lái)主要包括：對(duì)于穿線(xiàn)工程中，導(dǎo)管細(xì)，導(dǎo)線(xiàn)繁多造成管內(nèi)空間余量小，散熱面不夠。再加上施工人員技術(shù)素質(zhì)低，不能按圖施工。這樣的危害是加速了導(dǎo)線(xiàn)絕緣層的老化速度，降低了工程的使用壽命。沒(méi)有將腐蝕劑擦拭干凈，開(kāi)關(guān)處理沒(méi)有切斷相線(xiàn)，甚至將相線(xiàn)接到燈頭螺口線(xiàn)柱上。插座安裝將相線(xiàn)和零線(xiàn)位置互換，相線(xiàn)在上零線(xiàn)在下的規(guī)程接線(xiàn)問(wèn)題等是在接線(xiàn)工作中常見(jiàn)的**問(wèn)題。不少施工人員容易產(chǎn)生麻痹心理，在導(dǎo)管敷設(shè)施工中，對(duì)金屬材質(zhì)導(dǎo)管的管口不做處理，在管口處留很多毛刺，這些金屬毛刺是很大的**隱患：在穿線(xiàn)施工中這些毛刺容易將導(dǎo)線(xiàn)的絕緣層劃開(kāi)，后果不堪設(shè)想，一旦出現(xiàn)了問(wèn)題，輕者造成短路停電而且難以維修，重者可能引起火災(zāi)。在避雷系統(tǒng)施工過(guò)程中。引下線(xiàn)的做法各不相同，有的用鍍鋅圓鋼，有的利用構(gòu)造柱的四根主筋沿墻體或柱內(nèi)敷設(shè)。施工中如果漏焊也會(huì)留下很大的**隱患，其造成的后果是：漏接或者漏焊一處圓鋼，很可能就會(huì)使引下線(xiàn)失去應(yīng)有的作用，避雷系統(tǒng)就不能發(fā)揮正常作用。

For the electrical construction of buildings, there are many factors that can cause unsafe electrical construction. In summary, they mainly include: for the threading project, the pipe is thin and the wires are numerous, resulting in a small margin in the pipe and insufficient heat dissipation surface. In addition, the technical quality of the construction personnel is low, and the construction cannot be carried out according to the drawings. Such a hazard is to accelerate the aging speed of the wire insulation layer and reduce the service life of the project. The corrosive agent was not wiped clean, the switching process did not cut off the phase wire, and even the phase wire was connected to the screw thread post of the lamp cap. Socket installation interchanges the position of the phase line and the neutral line. The wiring problem with the phase line on the top and the neutral line on the bottom is a common safety problem in the wiring work. Many construction workers are prone to paralysis. In catheter laying facilities, the nozzles of metal catheters are not treated, leaving many burrs at the nozzles. These metal burrs are a big safety hazard: these burrs during threading construction It is easy to cut the insulation layer of the wire, and the consequences are unimaginable. Once a problem occurs, the lighter will cause a short circuit and the power will be difficult to repair, and the severer may cause a fire. During the construction of the lightning protection system.The methods of down-conducting are different. Some use galvanized round steel, and some use the four main bars of the structural column to lay along the wall or inside the column. If the welding is missed during the construction, it will also leave a big safety hazard. The consequence is: missed or missed welding of a round steel, it is very likely that the down conductor will lose its due role, and the lightning protection system will not be able to perform. Normal function.

1：漏電保護(hù)技術(shù)在建筑電氣工程中應(yīng)用原則

Application principles of leakage protection technology in building electrical engineering

1） 在接地保護(hù)原則方面。建筑電氣工程低壓系統(tǒng)的中性點(diǎn)一般不進(jìn)行接地，這樣在系統(tǒng)正常運(yùn)行過(guò)程中，須將電氣設(shè)備金屬外殼接地，同時(shí)供電設(shè)備的金屬外殼也須進(jìn)行接地保護(hù)。具體的內(nèi)容包括以下幾個(gè)方面：一，便攜式用電器具、移動(dòng)式用電器具金屬底座以及外殼、電壓器等電氣設(shè)備、傳動(dòng)設(shè)備都須進(jìn)行接地保護(hù)；二，汽油、柴油等金屬罐體外殼須進(jìn)行接地；三，建筑施工現(xiàn)場(chǎng)中，超過(guò)20厘米高度的電梯軌道、腳手架、起重折臂吊、豎井架等也須進(jìn)行接地保護(hù)；四，配電箱、配電屏柜、焊工工作平臺(tái)等也須進(jìn)行接地保護(hù)；五，在建筑施工現(xiàn)場(chǎng)中，電動(dòng)葫蘆、龍門(mén)吊、塔吊等軌道上，需要設(shè)置兩個(gè)或兩個(gè)以上的接地點(diǎn)。特別是對(duì)于軌道接頭處，須進(jìn)行電氣連接處理，將節(jié)點(diǎn)的電阻控制在4歐姆以?xún)?nèi)。如果軌道中有接地滑接器，那么需要通過(guò)連接線(xiàn)將接地滑接器與軌道合理地連接起來(lái)。第六，線(xiàn)路線(xiàn)桿上電氣設(shè)備金屬外殼以及支架須進(jìn)行接地處理。

1) In terms of the principle of grounding protection. The neutral point of the low-voltage system of building electrical engineering is generally not grounded, so during the normal operation of the system, the metal shell of the electrical equipment must be grounded, and the metal shell of the power supply equipment must also be grounded. The specific content includes the following aspects: first, portable electrical appliances, mobile electrical appliances, metal bases, housings, voltage transformers and other electrical equipment, transmission equipment must be grounded; second, gasoline, diesel and other metal tanks The body shell must be grounded; third, in the construction site, elevator tracks, scaffolds, hoisting jib cranes, masts, etc. that are more than 20 cm in height must also be grounded; fourth, power distribution boxes, power distribution panels , Welders’ work platforms, etc. must also be grounded. Fifth, in the construction site, two or more grounding points need to be set on electric hoists, gantry cranes, tower cranes and other tracks. Especially for track joints, electrical connection processing must be carried out, and the resistance of the node must be controlled within 4 ohms. If there is a grounding slider in the track, it is necessary to effectively connect the grounding slider to the track through a connecting wire. Sixth, the metal shells and brackets of electrical equipment on line poles must be grounded.

2） 在接零保護(hù)原則方面。在建筑電氣施工正常進(jìn)行過(guò)程中，一些電氣設(shè)備的不帶電外露部位，也需要進(jìn)行接零保護(hù)，具體包括以下幾個(gè)方面：一，配電屏、控制屏金屬框架部分需要進(jìn)行接零保護(hù)；二，電氣設(shè)備等傳動(dòng)設(shè)施須進(jìn)行接零保護(hù)；三，變壓器、發(fā)電機(jī)、照明工具、電動(dòng)工具等金屬外殼以及電容器金屬外殼等也須進(jìn)行接零進(jìn)行保護(hù)。四，線(xiàn)路線(xiàn)桿中金屬支架、開(kāi)關(guān)金屬外殼以及電容器金屬外殼等也須進(jìn)行接零保護(hù)；六，建筑施工現(xiàn)場(chǎng)電氣室中設(shè)備的金屬外殼、帶電部分金屬門(mén)、欄桿等等同樣需要接零保護(hù)。

1) In terms of the principle of zero protection. In the normal process of building electrical construction, some uncharged exposed parts of electrical equipment also need to be zero-connected protection, including the following aspects: First, the metal frame of the power distribution panel and control panel needs to be zero-connected protection; Second, electrical equipment and other transmission facilities must be protected against zero connection; third, metal casings such as transformers, generators, lighting tools, power tools, and capacitor metal casings must also be protected against zero connection. Fourth, the metal brackets in the line poles, switch metal shells, and capacitor metal shells must also be connected to zero protection; sixth, the metal shells of the equipment in the electrical room of the construction site, the metal doors of the live parts, the railings, etc. also need to be connected Zero protection.                                                                             

3） 建筑電氣安裝和施工配合原則。在建筑施工過(guò)程中，建筑安裝人員和施工人員在各道工序和各個(gè)工種之間密切配合、相互協(xié)作，改良施工環(huán)境，一樣同樣看待施工成果和對(duì)方施工成果，盡量做到不污染、不丟棄、不破壞，盡可能實(shí)現(xiàn)一次成型施工。如果是單項(xiàng)工程，則需要土建施工單位和建筑電氣安裝單位協(xié)作完成，土建施工單位逐項(xiàng)編制施工工序，雙方互相配合，制作科學(xué)合理的施工計(jì)劃和方案。電氣設(shè)備安裝和用電等是整個(gè)施工項(xiàng)目的重要部分，在施工過(guò)程中起著重要作用。因此，土建單位在指定施工進(jìn)度計(jì)劃時(shí)，需要考慮在施工過(guò)程中可能出現(xiàn)的問(wèn)題、建筑電氣安裝的相關(guān)問(wèn)題，并預(yù)留出足夠的電氣安裝工期，從而創(chuàng)造出良好的施工條件。  

3) Principles of building electrical installation and construction cooperation. In the process of building construction, construction installation personnel and construction personnel closely cooperate and cooperate with each other in various procedures and types of work to improve the construction environment. Discard, do not damage, and achieve one-time molding construction as much as possible. If it is a single project, it needs to be completed by the civil construction unit and the building electrical installation unit. The civil construction unit prepares the construction procedures item by item, and the two parties cooperate with each other to make a scientific and reasonable construction plan and plan. Specialties such as electrical equipment installation and electricity use are an important part of the entire construction project and play an important role in the construction process. Therefore, when the civil engineering unit specifies the construction schedule, it needs to consider the problems that may arise during the construction process and the related issues of the building electrical installation profession, and reserve enough electrical installation time to create good construction conditions.

2.現(xiàn)代建筑電氣漏電保護(hù)對(duì)策

Electric leakage protection countermeasures in modern buildings

1） 需安裝漏電保護(hù)器的場(chǎng)所。建筑工地施工環(huán)境復(fù)雜多半，用到的建筑材料種類(lèi)繁多。在一些潮濕的設(shè)備操作環(huán)境需安裝漏電保護(hù)措施，設(shè)備使用隨著建筑結(jié)構(gòu)的發(fā)展需要經(jīng)常移動(dòng)，很多電源端都是臨時(shí)的，往往忽略了漏電保護(hù)器的安裝，嚴(yán)重地威脅著操作人員的人身**，以及整個(gè)工程的穩(wěn)定進(jìn)展。腐蝕性和易燃物附近的用電設(shè)備需要加強(qiáng)**措施，根據(jù)不同場(chǎng)地的結(jié)構(gòu)，選取合適功能的附件，如采光點(diǎn)弱**通道較長(zhǎng)處，整個(gè)保護(hù)系統(tǒng)就需要安裝照明設(shè)備，一些大型設(shè)備在運(yùn)轉(zhuǎn)中不可以突然中止，阻斷設(shè)備的設(shè)計(jì)要求速度合理，要加強(qiáng)報(bào)警裝置的安放。建筑電氣導(dǎo)線(xiàn)分布復(fù)雜，交叉分部很容易造成高溫起火，在漏電保護(hù)方案的設(shè)計(jì)中，要考慮小販報(bào)警和保障應(yīng)急照明系統(tǒng)通電等問(wèn)題，確保**作業(yè)，提升建筑**質(zhì)量，為整個(gè)工程順利投入使用打好基礎(chǔ)。

1) Places where leakage protectors need to be installed. The construction environment of construction sites is mostly complex, and there are many kinds of building materials used. In some humid equipment operating environments, leakage protection measures need to be installed. The equipment needs to be moved frequently with the development of the building structure. Many power terminals are temporary, and the installation of leakage protectors is often ignored, which seriously threatens the personnel of the operators. Safety, and the steady progress of the entire project. Electrical equipment near corrosive and flammable materials needs to strengthen safety measures. According to the structure of different sites, select accessories with suitable functions. It is not allowed to stop suddenly during operation. The design of blocking equipment requires reasonable speed, and the placement of alarm devices should be strengthened. The distribution of electrical wires in buildings is complex, and the cross-sections are likely to cause high-temperature fires. In the design of the leakage protection scheme, issues such as hawker alarms and ensuring the power of emergency lighting systems must be considered to ensure safe operation, improve the safety quality of the building, and smoothly invest in the entire project Use a good foundation.

2） 漏電保護(hù)器動(dòng)作電流的選擇。單臺(tái)用電設(shè)備的漏電保護(hù)器，其動(dòng)作電流要四倍于正常運(yùn)行時(shí)的實(shí)測(cè)泄漏電流以上；配電線(xiàn)路中的漏電保護(hù)器，其動(dòng)作電流要大于正常運(yùn)行實(shí)測(cè)泄露電流的2.5倍，與此同時(shí)，還要保證大于泄漏電流較大的用電設(shè)備在正常運(yùn)行時(shí)泄漏電流的4倍。對(duì)于全方面進(jìn)行保護(hù)時(shí)，其動(dòng)作電流要2倍于實(shí)測(cè)泄漏電流，同時(shí)漏電保護(hù)器的額定動(dòng)作電流要有一定的過(guò)盈量，以滿(mǎn)足由于用電設(shè)備的增加、日久回路絕緣的電阻降低以及季節(jié)性的溫度辯護(hù)等導(dǎo)致電流泄漏的增加。

2) Selection of action current of the leakage protector. The operating current of the leakage protector of a single electrical equipment is four times or more than the measured leakage current during normal operation; the operating current of the leakage protector in the distribution line is greater than 2.5 times of the measured leakage current during normal operation, and At the same time, it is also necessary to ensure that the leakage current of the electrical equipment with the largest leakage current is 4 times that of the leakage current during normal operation. When protecting the whole network, its operating current should be twice as much as the measured leakage current. At the same time, the rated operating current of the leakage protector must have a certain amount of interference to meet the requirements of the increase in electrical equipment and the decrease in the resistance of the circuit insulation over time. And seasonal temperature defenses have led to increased current leakage.

3） 四極和二極漏電保護(hù)器的應(yīng)用。對(duì)于電氣**和基本要求準(zhǔn)則即為盡可能減少電器的觸頭數(shù)、極數(shù)和線(xiàn)路的連接點(diǎn)。線(xiàn)路的固定連接點(diǎn)和開(kāi)關(guān)觸頭等的活動(dòng)連接，在各種原因的影響下，都會(huì)由于導(dǎo)電**而引發(fā)事故。尤其是三相回路中的中性線(xiàn)，其導(dǎo)電**而引發(fā)的危險(xiǎn)更加嚴(yán)重，這是由于當(dāng)中性線(xiàn)導(dǎo)電**時(shí)，設(shè)備卻仍然在運(yùn)行，不易發(fā)現(xiàn)隱患，如果三相負(fù)荷發(fā)生嚴(yán)重不平衡，這將使三相電壓也趨于嚴(yán)重的不平衡狀態(tài)，進(jìn)而將單相設(shè)備燒壞，因此要盡可能地限制在中性線(xiàn)上增加觸頭。

3)Application of four-pole and two-pole leakage protector. The criterion for electrical safety and basic requirements is to minimize the number of contacts, poles, and connection points of electrical appliances. The fixed connection point of the line and the movable connection of the switch contact, etc., under the influence of various reasons, will cause accidents due to poor conduction. Especially for the neutral wire in the three-phase circuit, the danger caused by its poor conductivity is more serious. This is because when the neutral wire is poorly conductive, the equipment is still running and hidden dangers are not easy to find. If the three-phase load is severely unbalanced, This will make the three-phase voltage also tend to be in a serious unbalanced state, and then burn out the single-phase equipment, so it is necessary to limit the increase of contacts on the neutral line as much as possible.

4） 等電位聯(lián)結(jié)的實(shí)施。等電位聯(lián)結(jié)即為把保護(hù)接零總線(xiàn)和建筑物的暖通管、總煤氣管、總水管等金屬管道或裝置，用導(dǎo)線(xiàn)進(jìn)行聯(lián)結(jié)的一種方法，以此來(lái)均衡建筑物內(nèi)電位的目的，此法尤其適用于易燃易爆的場(chǎng)所。對(duì)于單相220V的線(xiàn)路，漏電保護(hù)器只能起到間接接觸保護(hù)作用，還同時(shí)存在由于機(jī)件的磨損、質(zhì)量的不穩(wěn)定引發(fā)的壽命較短、接觸**等因素的影響，導(dǎo)致動(dòng)作失靈等隱患，無(wú)法單獨(dú)作為一種合理的保護(hù)措施，仍需進(jìn)行等電位聯(lián)結(jié)，才能完全消掉低電位的金屬零件與漏電的設(shè)備或電氣線(xiàn)路之間的電火花、電弧現(xiàn)象的發(fā)生，進(jìn)而合理避免火災(zāi)等**事故。

4)Implementation of equipotential bonding. Equipotential bonding is a method of connecting the protective zero bus with metal pipes or devices such as building HVAC pipes, gas mains, water mains, etc. with wires to balance the potential in the building. This method is especially suitable for flammable and explosive places. For single-phase 220V lines, the leakage protector can only play the role of indirect contact protection. At the same time, it also has the influence of short life, poor contact and other factors caused by the abrasion of the mechanical parts and the instability of the quality, leading to hidden dangers such as operation failure. It cannot be used as an effective protective measure alone. Equipotential bonding is still needed to completely eliminate the occurrence of electric sparks and arcs between low-potential metal parts and leakage equipment or electrical circuits, thereby effectively avoiding fires and other safety accident.

5） 漏電保護(hù)器的使用要注意的問(wèn)題

① 漏電保護(hù)器額定漏電動(dòng)作電流的協(xié)調(diào)配合

在就地用電負(fù)荷保護(hù)的漏電保護(hù)器，其額定的漏電動(dòng)作電流IΔn1須滿(mǎn)足IΔn1≤30mA的這一條件；干線(xiàn)或分支線(xiàn)保護(hù)的漏電保護(hù)器，其額定的漏電動(dòng)作電流IΔn2的前提是IΔn2≥1.25IΔn1；主干線(xiàn)或總干線(xiàn)保護(hù)的漏電保護(hù)器哦，其額定的漏電動(dòng)作電流IΔn3通常是300mA,按照相應(yīng)標(biāo)準(zhǔn)，其前提條件為300mA≥IΔn3≥1.25IΔn2。所以，總結(jié)來(lái)說(shuō)，漏電保護(hù)器的使用條件可歸納為300mA≥IΔn3≥1.25IΔn2、IΔn2≥1.25IΔn1、IΔn1≤30mA。

②  漏電保護(hù)器額定動(dòng)作時(shí)間的協(xié)調(diào)配合

首先，根據(jù)《漏電保護(hù)器安裝運(yùn)行規(guī)程》中的相關(guān)標(biāo)準(zhǔn)，上下級(jí)漏電保護(hù)器額定動(dòng)作時(shí)間的級(jí)差處于0.2s，作為快速型的是處于末端保護(hù)漏電保護(hù)器的額定值，通常都小于0.1s，而二級(jí)和三級(jí)的漏電保護(hù)器的額定值則有所延伸，其延伸值分別為0.2s和0.4s。再者將漏電保護(hù)器的反時(shí)限延的特殊性加以運(yùn)用，比如①級(jí)比二級(jí)少0.1s，三級(jí)則須加時(shí)0.2s。結(jié)尾，如果建筑工地選用的漏電保護(hù)器屬于反時(shí)限型，則可以將日本現(xiàn)行使用標(biāo)準(zhǔn)作為參照進(jìn)行使用。若漏電電流為IΔn，動(dòng)作時(shí)間處于0.2~1s之間；若漏電電流為1.4IΔn，動(dòng)作時(shí)間則處于0.1s和0.5s之間；若漏電電流為4.4IΔn，動(dòng)作時(shí)間在0.05s以?xún)?nèi)。

5) Issues that should be paid attention to in the use of leakage protectors

①Coordination of the rated leakage current of the leakage protector

In the leakage protector for on-site electrical load protection, the rated leakage current IΔn1 must meet the condition of IΔn1≤30mA; for the leakage protector for main or branch line protection, the premise of the rated leakage current IΔn2 is IΔn2 ≥1.25IΔn1; The leakage protector for main trunk line or main trunk line protection, its rated leakage action current IΔn3 is usually 300mA, according to the corresponding standard, the prerequisite is 300mA≥IΔn3≥1.25IΔn2. Therefore, in summary, the operating conditions of the leakage protector can be summarized as 300mA≥IΔn3≥1.25IΔn2, IΔn2≥1.25IΔn1, IΔn1≤30mA.

② Coordination of the rated operating time of the leakage protector

First of all, according to the relevant standards in the "Earth-leakage Protector Installation and Operation Regulations", the difference in the rated operating time of the upper and lower-level leakage protectors is 0.2s. As a fast type, the rated value of the terminal protection leakage protector is usually less than 0.1s. , And the ratings of the secondary and tertiary leakage protectors have been extended, and the extension values are 0.2s and 0.4s respectively. In addition, the special nature of the inverse time delay of the leakage protector is used. For example, the first level is 0.1s less than the second level, and the third level must be 0.2s longer. Finally, if the leakage protector selected at the construction site is of the inverse time limit type, you can use the current Japanese standard for use as a reference. If the leakage current is IΔn, the action time is between 0.2 and 1s; if the leakage current is 1.4IΔn, the action time is between 0.1s and 0.5s; if the leakage current is 4.4IΔn, the action time is within 0.05s.

3. 產(chǎn)品概述General product

常見(jiàn)的相與相間發(fā)生短路可以產(chǎn)生很大電流，可采用開(kāi)關(guān)保護(hù)，而發(fā)生人體觸電、線(xiàn)路老化而導(dǎo)致的電流泄露產(chǎn)生的火災(zāi)以及設(shè)備的接地故障都是由于漏電流所造成，漏電流一般都在30mA-3A，這些值很小，傳統(tǒng)開(kāi)關(guān)無(wú)法進(jìn)行保護(hù)，所以須采用剩余電流動(dòng)作保護(hù)裝置。

剩余電流繼電器是由剩余電流互感器來(lái)檢測(cè)剩余電流，并在規(guī)定條件下，當(dāng)剩余電流達(dá)到或超過(guò)給定值時(shí)，使電器的一個(gè)或多個(gè)電氣輸出電路中的觸點(diǎn)產(chǎn)生開(kāi)閉動(dòng)作的開(kāi)關(guān)電器。

下面介紹三種常見(jiàn)的漏電情況。

1、防直接接觸電擊須采用I△n≤30mA的高靈敏度的RCD。

The common phase-to-phase short circuit can generate a large current, which can be protected by a switch. However, the current leakage caused by human body electric shock and line aging and the ground fault of the equipment are caused by leakage current. The leakage current is generally At 30mA-3A, these values are so small that traditional switches cannot be protected, so a residual current-operated protection device must be used.

The residual current relay is a residual current transformer to detect the residual current, and under specified conditions, when the residual current reaches or exceeds a given value, one or more electrical output circuit contacts in the electrical appliance will be opened and closed. Switch electrical appliances.

Here are three common leakage situations.

1. High-sensitivity RCD with I△n≤30mA must be used to prevent direct contact and electric shock.

2、防間接接觸電擊可采用I△n大于30mA的中靈敏度的RCD。

2. The medium sensitivity RCD with I△n greater than 30mA can be used to prevent indirect contact electric shock.

3、防火RCD需采用4極或2極RCD。

3.  4-pole or 2-pole RCD shall be used for fireproof RCD.

對(duì)于IT系統(tǒng)，按規(guī)定采用剩余電流繼電器。為防止系統(tǒng)絕緣降低和作為二次故障后備保護(hù)，依據(jù)接線(xiàn)型式，采用類(lèi)似 TT 或 TN 系統(tǒng)的保護(hù)措施。首先應(yīng)采用絕緣監(jiān)視裝置，預(yù)測(cè)一次故障。

For IT systems, residual current relays are used as required. In order to prevent the insulation of the system from degrading and as a secondary fault backup protection, according to the wiring type, a protective measure similar to the TT or TN system is adopted. First, an insulation monitoring device should be used to predict a failure.

對(duì)于TT系統(tǒng)，推薦采用剩余電流繼電器。因?yàn)楫?dāng)發(fā)生單相接地故障時(shí)，故障電流很小，且較難估計(jì)，達(dá)不到開(kāi)關(guān)的動(dòng)作電流，外殼上將出現(xiàn)危險(xiǎn)電壓。此時(shí)N線(xiàn)須穿過(guò)剩余電流互感器。

For the TT system, a residual current relay is recommended. Because when a single-phase grounding fault occurs, the fault current is very small and difficult to estimate. If the operating current of the switch is not reached, a dangerous voltage will appear on the housing. At this time, the N wire must pass through the residual current transformer.

對(duì)于TN-S系統(tǒng)，可采用剩余電流繼電器。更快速靈敏切斷故障，以提高**可靠性，此時(shí) PE 線(xiàn)不得穿過(guò)互感器，N 線(xiàn)須穿互感器，且不得重復(fù)接地。

For the TN-S system, a residual current relay can be used. Cut off the fault more quickly and sensitively to improve safety and reliability. At this time, the PE wire must not pass through the transformer, and the N wire must pass through the transformer, and it must not be grounded repeatedly.

對(duì)于TN-C系統(tǒng)，不能采用剩余電流繼電器。因?yàn)?PE 線(xiàn)和 N 線(xiàn)合一，若 PEN 線(xiàn)不重復(fù)接地，當(dāng)外殼帶電，互感器進(jìn)出電流相等，ASJ拒動(dòng)；若PEN線(xiàn)重復(fù)接地，部分單相電流將流入重復(fù)接地，達(dá)一定值后，ASJ 誤動(dòng)。 需將TN-C系統(tǒng)改造成TN-C-S系統(tǒng)，同TN-S系統(tǒng)，再將剩余電流互感器接入TN-S系統(tǒng)中。

For TN-C systems, residual current relays cannot be used. Because the PE wire and the N wire are integrated, if the PEN wire is not repeatedly grounded, when the housing is energized, the current in and out of the transformer is equal, and the ASJ refuses to move; if the PEN wire is repeatedly grounded, part of the single-phase current will flow into the repeated grounding. After reaching a certain value, ASJ malfunctioned. It is necessary to transform the TN-C system into a TN-C-S system, which is the same as the TN-S system, and then connect the residual current transformer to the TN-S system.