摘要：保護漏電設(shè)備的作用主要就是避免直接或者是間接的接觸到通電設(shè)備，這也是**通電的必要舉措。就建筑工地用電的基本要求來說，探討了施工地的保護漏電設(shè)備在投入使用中面臨的問題，同時進行提升，這樣能夠合理地減少事故的出現(xiàn)，也是保障施工中用電通暢的必然要求。

關(guān)鍵詞：漏電保護；建筑工地；電氣**

Abstract: The main function of protecting leakage equipment is to avoid direct or indirect contact with energized equipment, which is also a necessary measure for safety. As far as the basic requirements for electricity use on construction sites are concerned, the problems faced by the leakage protection equipment of the construction site during the putting into use are discussed, and at the same time, it can be upgraded. This can effectively reduce the occurrence of accidents and is also an inevitable requirement for ensuring the smooth use of electricity during construction. .

Keywords: leakage protection; construction site; electrical safety

0：概述General

  施工地是使用強制性的裝置保護漏電設(shè)備，目的就是確保施工地供電**。在正常的施工中，由于施工現(xiàn)場特殊，經(jīng)常會使漏電保護裝置跳閘，在阻礙施工進程的同時還危害了施工現(xiàn)場的**。將施工地的實際情況和用電情況相結(jié)合，概括出在施工地保護漏電設(shè)備時常跳閘的現(xiàn)象，并且給予了保護漏電設(shè)備的日常保護措施。

  保護漏電設(shè)備的主要作用就是通電設(shè)備在出現(xiàn)漏電的情況或者是在人體觸電的時候出現(xiàn)致命危險的過程進行相應(yīng)的保護，其設(shè)備主要由開關(guān)、實驗按鍵、脫口裝置，脫口整體結(jié)構(gòu)、剩余電流互感器等幾個部件組成。進行保護設(shè)施在接地的故障電流是介于保護漏電設(shè)備漏電的脫口設(shè)備上，并且超出預(yù)定數(shù)值時，主開關(guān)會自動跳閘，出現(xiàn)故障的電流被切斷，在一定程度上起到了保護的作用。

  在施工現(xiàn)場，通常來說用電標準都達不到要求，所投入使用的設(shè)施與線路存在很多的**問題，主要特點就是由較強流動性、多次重復(fù)性、臨時性。

The construction site is to use compulsory devices to protect the leakage equipment, the purpose is to ensure the safety of power supply at the construction site. Due to the special construction site, the leakage protection device is often tripped, which not only hinders the construction process, but also endangers the safety of the construction site. Combining the actual situation of the construction site with the electricity usage, the phenomenon of frequent tripping of the leakage protection equipment at the construction site is summarized, and daily protective measures to protect the leakage equipment are given.

The main function of the protection of leakage equipment is to protect the energized equipment in the process of leakage or fatal danger when the human body gets an electric shock. The equipment is mainly composed of switches, experimental buttons, talkers, the overall structure of the talk, and residual current mutual inductance. It is composed of several components such as a device. The grounding fault current of the protective equipment is between the leaking equipment that protects the leakage equipment, and when it exceeds the predetermined value, the main switch will automatically trip, and the fault current is cut off, which plays a protective role to a certain extent.

At the construction site, generally speaking, the electricity standards are not up to the requirements, and the facilities and lines put into use have many safety problems. The main characteristics are strong fluidity, multiple repetitions, and temporary nature.

1：施工現(xiàn)場漏電保護器誤動作的原因Causes of wrong action of leakage protector on construction site

1） 外界干擾。 External interference.

a) 雷擊時正逆交變過程引起的過電壓，通過架空線路、絕緣電線、電纜和電氣涉筆的對地電容，產(chǎn)生對地泄漏電流，使剩余電流保護器發(fā)生誤動作，甚至直接損壞。過高時將造成保護器電源和內(nèi)部電路的損害，帶有失壓脫扣器的自動開關(guān)脫扣線圈燒壞；過低時會引起失壓脫扣線圈開關(guān)跳閘，合閘控制回路不能啟動、帶有機械閉鎖裝置的電磁開關(guān)因吸跳功率不足，使脫扣速度緩慢或拒動。

a) The over voltage caused by the positive and negative alternating process during lightning strikes, through overhead lines, insulated wires, cables and the ground capacitance of the electrical pen, generates leakage current to the ground, causing the residual current protector to malfunction or even directly damage. If it is too high, it will cause damage to the protector power supply and internal circuit, and the automatic switch trip coil with the loss-of-voltage release will burn out; The electromagnetic switch with mechanical locking device has insufficient suction power, which makes the tripping speed slow or refuses to move.

b) 鋪設(shè)的各種線路與投入使用的用電設(shè)備在施工地進行照明的過程中出現(xiàn)了線路的亂搭亂建的情況，造成了線路的提前老化、線路與通電設(shè)施的絕緣電阻降低、電流泄漏甚至是出現(xiàn)接地的情況，造成了漏電保護設(shè)備多次出現(xiàn)狀況影響正常的使用。因為漏電開關(guān)的輸出終端的線路的絕緣電阻降低與接地線接零線的保護，在進行漏電保護裝置安裝過程中，電源的中性點沒有接地。在出現(xiàn)觸電情況的過程中降低了靈敏程度和拒動的現(xiàn)象。

b) During the process of lighting the construction site, the various lines laid and the electrical equipment put into use have been randomly constructed, which has caused the premature aging of the line, the reduction of the insulation resistance of the line and the energized facilities, and the current Leakage or even grounding has caused the leakage protection equipment to appear repeatedly and affect normal use. Because the insulation resistance of the circuit of the output terminal of the leakage switch is reduced and the grounding line is connected to the neutral line, the neutral point of the power supply is not grounded during the installation of the leakage protection device. In the process of electric shock, the sensitivity and refusal to move are reduced.

c) 環(huán)境變化干擾，這里較主要的使指環(huán)境條件，例如夏季溫度升高，雨季溫潤潮濕；或者是漏電保護裝置周圍安裝了帶有強烈振幅的電氣設(shè)施；或者是在運行的過程中 長期受有害氣體的不斷腐蝕與侵蝕；使得漏電保護設(shè)施的電子組件的電磁圈與組成結(jié)構(gòu)等的絕緣程度下降、出現(xiàn)霉斷與銹蝕的情況，終使得漏電保護設(shè)施出現(xiàn)錯誤舉動或者是拒動。

c)Environmental change interference, the most important factor here refers to environmental conditions, such as increased temperature in summer and warm and humid rainy season; or electrical equipment with strong amplitude installed around the leakage protection device; or long-term exposure to harmful gases during operation The continuous corrosion and erosion of the leakage protection device; the insulation degree of the electromagnetic coil and the composition structure of the electronic component of the leakage protection facility is reduced, and the situation of mold breakage and rust occurs, and finally the leakage protection facility is wrongly acted or refused to act.

2） 漏電保護器接線錯誤。漏電保護器安裝時，往往因接線錯誤或安裝方式與線路結(jié)構(gòu)不適應(yīng)因發(fā)誤動作、拒動或達不到較佳效果。中性線穿過漏電保護器后，同其他漏電保護器的中性線或與其他沒有裝設(shè)漏電保護器的中性線連在一起；中性線斷線或接觸**，致使中點電位偏移零電位；這些增加了中性線漏電和引發(fā)其他故障的幾率。

2) The wiring of the leakage protector is wrong. When the leakage protector is installed, it is often caused by incorrect wiring or inappropriate installation method and circuit structure due to misoperation, refusal to move, or failure to achieve the best effect. After the neutral line passes through the leakage protector, it is connected with the neutral line of other leakage protectors or with other neutral lines that are not equipped with a leakage protector; the neutral line is broken or poorly connected, causing the neutral point to be biased. Shift the zero potential; these increase the probability of neutral line leakage and other failures.

3） 漏電保護器選型不合理。通過額定漏電的流經(jīng)電流大于30mA或者大于通電設(shè)備標準電流2倍的保護漏電設(shè)備，或者是挑選有延時效果的保護漏電設(shè)備，因為額定漏電的流經(jīng)電流不斷提高或者是靈敏程度的降低，使得漏電事故在發(fā)生的同時，末端的漏電保護設(shè)備沒有運行，上級的保護漏電設(shè)備就會開始動作。

3) The selection of the leakage protector is not suitable. Protect leakage devices with a rated leakage current greater than 30mA or more than twice the standard current of the energized device, or choose a protective leakage device with a delay effect, because the current flowing through the rated leakage continues to increase or the sensitivity is reduced, When the leakage accident occurs, the leakage protection equipment at the end is not operating, and the higher-level leakage protection equipment will start to operate.

4） 漏電保護器本身的問題。4) The problem of the leakage protector.

a) 固有的局限性。 目前的漏電保護器，不論是電磁型還是電子型均采用磁感應(yīng)互感器拾取用電設(shè)備主回路中的漏電流，三相或者三相四線在磁環(huán)中不可能布置完全均衡，在施工現(xiàn)場有較多的電焊機等雙相或者單相負荷，三相電流也不可能完全平衡，甚至?xí)嗖詈艽?，這個電動勢大到一定程度就會導(dǎo)致漏電保護器跳閘。

a) Inherent limitations. The current leakage protector, whether electromagnetic or electronic, uses magnetic induction transformers to pick up the leakage current in the main circuit of electrical equipment. It is impossible to arrange three-phase or three-phase four-wire in the magnetic ring to be completely balanced. For more two-phase or single-phase loads such as electric welding machines, the three-phase currents cannot be completely balanced, and may even differ greatly. If the electromotive force is too large to a certain extent, it will cause the leakage protector to trip.

b) 質(zhì)量差、參數(shù)配置不當。施工現(xiàn)場并沒有根據(jù)相關(guān)的施工規(guī)范要求以及施工計劃方案來進行漏電保護設(shè)備的購入，并且因為購入的漏電保護器自身的質(zhì)量低下，內(nèi)部的實際情況與標準的參數(shù)標準不相符，剛投入使用的新產(chǎn)品就出現(xiàn)了誤動作的情況。

b) Poor quality and improper parameter configuration. The construction site did not purchase leakage protection equipment in accordance with relevant construction specifications and construction plans, and because the quality of the purchased leakage protector itself was low, the actual internal situation did not match the standard parameter standards, just put it into operation The new product used has malfunctioned.

2.施工現(xiàn)場科學(xué)使用漏電保護器的方法Methods of using leakage protector scientifically on construction site

在提升施工**的管理問題的同時還須加強對施工電工人員的知識培訓(xùn)，所采取的預(yù)防方式須結(jié)合實際情況與施工技術(shù)來指定。

While improving the management of construction safety, it is also necessary to strengthen the knowledge training of construction electricians, and the prevention methods adopted must be specified in accordance with the actual situation and construction technology.

1） 避免外界干擾。避免雷電過電壓干擾引起誤動作的措施除在架空線路上安裝避雷器或擊穿間隙，及在總配電箱處安裝150mA，0.2s的延時型漏電斷路器外，為了防止中性點位移過電壓損壞或降低漏電斷路器的靈敏度，還應(yīng)調(diào)整負載，使之盡可能均勻地分布在三相線上，調(diào)換分支線相序，減小三相絕緣電阻不平衡電流，交換中性線，使導(dǎo)線截面積不小于各相線的導(dǎo)線截面。

1)Avoid external interference.Measures to avoid malfunction caused by lightning over voltage interference include installing lightning arresters or breakdown gaps on overhead lines, and installing 150mA, 0.2s delay type leakage circuit breakers at the main distribution box, in order to prevent excessive neutral point displacement If the voltage is damaged or the sensitivity of the leakage circuit breaker is reduced, the load should be adjusted to distribute it on the three-phase line as evenly as possible. The cross-sectional area of the conductor shall not be less than the cross-section of the conductor of each phase line.

2） 正確選配安裝接線

a) 選配須與線路相適應(yīng)。漏電開關(guān)的額定電壓、額定電流、分斷能力等性能指標應(yīng)與線路條件相適應(yīng)。電源干線保護用漏電保護器和終端設(shè)備用漏電保護器的耐受電壓有所不同。電源干線和終端發(fā)生金屬性接地故障時所產(chǎn)生的故障電流可相差幾倍。

b) 實行分級分區(qū)保護。把整個施工場地根據(jù)專業(yè)與不同的相鄰施工團隊分布成不同的漏電保護設(shè)備區(qū)域，每一個保護區(qū)域之內(nèi)都須有一套完整的二級漏電的保護設(shè)施，這樣在一定程度之內(nèi)能夠提升整個保護區(qū)域的靈敏程度，并且還能減少保護漏電設(shè)置出現(xiàn)跳閘情況的幾率，減少因故障出現(xiàn)停電的現(xiàn)象

c) 嚴格區(qū)分中性線和保護線。漏電保護器標有負荷側(cè)和電源側(cè)時，應(yīng)按規(guī)定安裝接線，不得反接。三級四線式或四極式漏電保護器的中性線應(yīng)接入漏電保護器，經(jīng)過漏電保護器的中性線不得作為保護線、不能重復(fù)接地或接設(shè)備外露可導(dǎo)電部分。負荷側(cè)的中性線不得與其他回路共用。

2) Correctly select and install wiring

a) The selection must be compatible with the line. The performance indicators such as the rated voltage, rated current, and breaking capacity of the leakage switch should be adapted to the line conditions. The withstand voltage of the leakage protector for mains protection and the leakage protector for terminal equipment is different. When a metallic ground fault occurs in the mains of the power supply and the terminal, the fault current generated can be several times different.

b) Implement hierarchical and zoned protection. The entire construction site is distributed into different leakage protection equipment areas according to majors and different adjacent construction teams. Each protection area must have a complete set of secondary leakage protection facilities, which can improve the entire The sensitivity of the protection area can also reduce the probability of tripping of the protection leakage setting, and reduce the phenomenon of power outage due to faults

c) Strictly distinguish between neutral line and protection line. When the leakage protector is marked with the load side and the power side, the wiring should be installed according to the regulations, and no reverse connection is allowed. The neutral line of the three-level four-wire or four-pole leakage protector should be connected to the leakage protector. The neutral line passing through the leakage protector shall not be used as a protection line, and it cannot be repeatedly grounded or connected to the exposed conductive parts of the equipment. The neutral line on the load side must not be shared with other circuits.

3. 產(chǎn)品概述General product

常見的相與相間發(fā)生短路可以產(chǎn)生很大電流，可采用開關(guān)保護，而發(fā)生人體觸電、線路老化而導(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)開關(guān)無法進行保護，所以須采用剩余電流動作保護裝置。

剩余電流繼電器是由剩余電流互感器來檢測剩余電流，并在規(guī)定條件下，當剩余電流達到或超過給定值時，使電器的一個或多個電氣輸出電路中的觸點產(chǎn)生開閉動作的開關(guān)電器。

下面介紹三種常見的漏電情況。

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、防直接接觸電擊須采用I△n≤30mA的高靈敏度的RCD。

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 is required for fire-resistant RCD.

對于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，依據(jù)接線型式，采用類似 TT 或 TN 系統(tǒng)的保護措施。首先應(yīng)采用絕緣監(jiān)視裝置，預(yù)測一次故障。

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.

對于TT系統(tǒng)，推薦采用剩余電流繼電器。因為當發(fā)生單相接地故障時，故障電流很小，且較難估計，達不到開關(guān)的動作電流，外殼上將出現(xiàn)危險電壓。此時N線須穿過剩余電流互感器。

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 PE 線不得穿過互感器，N 線須穿互感器，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.

對于TN-C系統(tǒng)，不能采用剩余電流繼電器。因為 PE 線和 N 線合一，若 PEN 線不重復(fù)接地，當外殼帶電，互感器進出電流相等，ASJ拒動；若PEN線重復(fù)接地，部分單相電流將流入重復(fù)接地，達一定值后，ASJ 誤動。 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.

4.產(chǎn)品簡介Product description

安科瑞電氣ASJ系列剩余電流繼電器能夠滿足上述幾種漏電情況的防護，與遙控跳閘開關(guān)聯(lián)用，及時切斷電源，防止間接接觸、限制漏電電流。也可以直接作為信號繼電器，監(jiān)控電力設(shè)備。特別適用于學(xué)校、商廈、工廠車間、集貿(mào)市場、工礦企業(yè)、國家著重消防單位、智能大廈與小區(qū)，地鐵、石油化工、電信及國防等部門用電的**保護。

ASJ系列產(chǎn)品主要有兩種安裝方式，ASJ10系列為導(dǎo)軌安裝，外形和功能如下表所示：

Acrel Electric's ASJ series residual current relay can meet the protection of the above-mentioned leakage conditions. It can be used in conjunction with a remote trip switch to cut off the power supply in time to prevent indirect contact and limit the leakage current. It can also be directly used as a signal relay to monitor power equipment. It is especially suitable for the safety protection of electricity consumption in schools, commercial buildings, factory workshops, bazaars, industrial and mining enterprises, national key fire-fighting units, smart buildings and communities, subways, petrochemicals, telecommunications and national defense departments.

There are two main installation methods for ASJ series products. ASJ10 series are rail-mounted installations. The shape and functions are shown in the following table:

外形	型號	主要功能	功能差異
	ASJ10-LD1C	1、剩余電流測量 2、越限告警 3、額定剩余動作電流可設(shè)定 4、極限不驅(qū)動時間可設(shè)定 5、兩組繼電器輸出 6、具有就地/遠程測試/復(fù)位功能	1、AC型剩余電流測量 2、電流越限報警指示
	ASJ10-LD1A		1、A型剩余電流測量 2、電流百分比光柱顯示
	ASJ10L-LD1A		1、A型剩余電流測量 2、段碼液晶顯示 3、互感器斷線報警 4、預(yù)報警值可設(shè)，返回值可設(shè) 5、25條事件記錄

Shape	Model	Function	Difference
	ASJ10-LD1C	1. Residual current measurement 2. Over-limit alarm 3. The rated residual operating current can be set 4. The limit non-driving time can be set 5. Two sets of relay output 6. With local/remote test/reset function	1. AC type residual current measurement 2. Current limit alarm indication
	ASJ10-LD1A		1. A type residual current measurement 2. Current percentage bar display
	ASJ10L-LD1A		1. A type residual current measurement 2. Segment LCD display 3. Transformer disconnection alarm 4. Pre-alarm value can be set, return value can be set 5. 25 event records

ASJ20系列為面板安裝，外形和功能如下表所示：

ASJ20 series are panel mounted, the shape and functions are shown in the following table:

外形	型號	主要功能	功能差異
	ASJ20-LD1C	1、剩余電流測量 2、越限告警 3、額定剩余動作電流可設(shè)定 4、極限不驅(qū)動時間可設(shè)定 5、兩組繼電器輸出 6、具有就地/遠程測試/復(fù)位功能	1、AC型剩余電流測量 2、電流越限報警指示
	ASJ20-LD1A		1、A型剩余電流測量 2、電流百分比光柱顯示

其中AC型和A型剩余電流繼電器的區(qū)別是：AC型剩余電流繼電器是對突然施加或緩慢上升的剩余正弦交流電流能確保脫扣的剩余電流繼電器，主要監(jiān)測正弦交流信號。A型剩余電流繼電器是對突然施加的或緩慢上升的剩余正弦交流電流和剩余脈動直流電流能確保脫扣的剩余電流繼電器，主要監(jiān)測正弦交流信號和脈沖直流信號。 

儀表具體的接線端子和典型接線如下所示：

The difference between AC type and A type residual current relay is: AC type residual current relay is a residual current relay that can ensure the tripping of residual sinusoidal AC current that is suddenly applied or slowly rising, and mainly monitors sinusoidal AC signals. The A type residual current relay is a residual current relay that can ensure the tripping of the residual sinusoidal alternating current and residual pulsating direct current that is applied suddenly or slowly. It mainly monitors the sinusoidal alternating current signal and the pulsed direct current signal.

The specific wiring terminals and typical wiring of the instrument are as follows:

5.結(jié)語Summary

保護漏電的裝置在對人體無意識地接觸通電設(shè)備導(dǎo)致觸電的體況下預(yù)防，能夠合理地減少造成的傷害，對于因為電弧性的接地情況而導(dǎo)致的電氣方面的火災(zāi)有很好的預(yù)防效果。ASJ系列剩余電流繼電器產(chǎn)品能夠監(jiān)測線路中的漏電流，當漏電流達到或者超過設(shè)定值時，內(nèi)部繼電器動作，發(fā)出告警，并能與斷路器開關(guān)聯(lián)動，快速切斷線路，保證線路**。

The leakage protection device can prevent the human body from unconsciously contacting the energized equipment and causing electric shock, which can effectively reduce the damage caused, and has a good preventive effect on electrical fires caused by arc grounding. ASJ series residual current relay products can monitor the leakage current in the line. When the leakage current reaches or exceeds the set value, the internal relay will act to issue an alarm, and can be linked with the circuit breaker switch to quickly cut off the line to ensure line safety.

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