電(dian)氣(qi)設(she)備(bei)的接(jie)(jie)(jie)地(di)部分則是(shi)正常(chang)情況下不帶電(dian)的金屬導(dao)體，一般為金屬外(wai)殼。電(dian)氣(qi)設(she)備(bei)接(jie)(jie)(jie)地(di)裝置由接(jie)(jie)(jie)地(di)體和接(jie)(jie)(jie)地(di)線(xian)組(zu)成。與(yu)(yu)土壤直(zhi)接(jie)(jie)(jie)接(jie)(jie)(jie)觸的金屬體稱為接(jie)(jie)(jie)地(di)體；連接(jie)(jie)(jie)電(dian)氣(qi)設(she)備(bei)與(yu)(yu)接(jie)(jie)(jie)地(di)體之間的導(dao)線(xian)（或導(dao)體）稱為接(jie)(jie)(jie)地(di)線(xian)。
　　1.1安全保(bao)護接(jie)地(di)(di)。主要包括：為(wei)(wei)防(fang)止(zhi)(zhi)電(dian)力(li)設(she)(she)施或電(dian)子(zi)電(dian)氣(qi)設(she)(she)備(bei)絕緣損壞(huai)、危(wei)及人身安全而(er)(er)設(she)(she)置的(de)(de)保(bao)護接(jie)地(di)(di)；為(wei)(wei)消除生(sheng)(sheng)產過程中產生(sheng)(sheng)的(de)(de)靜電(dian)積累，引起(qi)觸電(dian)或爆炸而(er)(er)設(she)(she)的(de)(de)靜電(dian)接(jie)地(di)(di)；為(wei)(wei)防(fang)止(zhi)(zhi)電(dian)磁感應(ying)而(er)(er)對設(she)(she)備(bei)的(de)(de)金屬外(wai)殼(ke)、屏(ping)蔽罩(zhao)或屏(ping)蔽線外(wai)皮(pi)所進(jin)行(xing)的(de)(de)屏(ping)蔽接(jie)地(di)(di)。其中保(bao)護接(jie)地(di)(di)應(ying)用最為(wei)(wei)廣泛，它將(jiang)機（外(wai)）殼(ke)接(jie)地(di)(di)。此種接(jie)地(di)(di)的(de)(de)目的(de)(de)是為(wei)(wei)了安全。
　　1.2系統接地(di)。這種(zhong)(zhong)接地(di)給電路系統提供一個基準電位（電位），同時(shi)也(ye)可將(jiang)千擾(rao)引走。此(ci)種(zhong)(zhong)接地(di)目的是為了抵制外部(bu)的千擾(rao)。
　　1.3防雷(lei)接地。為防止(zhi)雷(lei)電(dian)過電(dian)壓(ya)對(dui)人身或設(she)備產生危害，而設(she)置的過電(dian)壓(ya)保(bao)護設(she)備的接地，稱為防雷(lei)接地，如避雷(lei)針、避雷(lei)器的接地。
　　1.4重(zhong)復接(jie)地。在低壓配電系統(tong)的(de)(de)系統(tong)中(zhong)(zhong)，為防止(zhi)因(yin)中(zhong)(zhong)性(xing)線(xian)故(gu)障而(er)失去接(jie)地保護(hu)作用，造成電擊危險和損壞設(she)備，對(dui)中(zhong)(zhong)性(xing)線(xian)進(jin)行重(zhong)復接(jie)地。系統(tong)中(zhong)(zhong)的(de)(de)重(zhong)復接(jie)地點為：架空線(xian)路的(de)(de)終(zhong)端及線(xian)路中(zhong)(zhong)適當點；四芯電纜(lan)的(de)(de)中(zhong)(zhong)性(xing)線(xian)；電纜(lan)或(huo)架空線(xian)路在建筑物或(huo)車間的(de)(de)進(jin)線(xian)處。
　　1.5防靜電接(jie)地(di)。為了消(xiao)除靜電對人身和設備產生(sheng)危害而進行(xing)的接(jie)地(di)，如將某些液(ye)體(ti)或(huo)氣體(ti)的金屬輸(shu)送管道或(huo)車輛的接(jie)地(di)。
　　1.6屏(ping)蔽接地。為防止(zhi)電氣(qi)設備(bei)(bei)因受電磁千(qian)(qian)擾，而(er)影響其(qi)(qi)工作或對其(qi)(qi)他設備(bei)(bei)造成電磁千(qian)(qian)擾的屏(ping)蔽設備(bei)(bei)的接地。
　　我們往(wang)往(wang)只知道接(jie)地可防(fang)止(zhi)(zhi)(zhi)人身(shen)遭受(shou)電擊(ji)，其實接(jie)地除(chu)了這一作用(yong)外，還(huan)可以防(fang)止(zhi)(zhi)(zhi)設備和線路遭受(shou)損(sun)(sun)壞、預防(fang)火災、防(fang)止(zhi)(zhi)(zhi)雷擊(ji)、防(fang)止(zhi)(zhi)(zhi)靜電損(sun)(sun)害和保*電力系統的(de)正常運行(xing)。
　　2.1防止(zhi)電(dian)(dian)擊(ji)。人(ren)(ren)體阻抗和所處環境(jing)的(de)狀(zhuang)況有極大的(de)關系，環境(jing)越潮濕，人(ren)(ren)體的(de)阻抗越低(di)，也越容易遭受電(dian)(dian)擊(ji)。例如(ru)，自裝過(guo)交流收(shou)音機的(de)人(ren)(ren)幾乎(hu)都受到過(guo)電(dian)(dian)擊(ji)，但幾乎(hu)都能擺脫電(dian)(dian)源，因為此時人(ren)(ren)所處的(de)環境(jing)千燥，皮膚(fu)也較千燥。接地是防止(zhi)電(dian)(dian)擊(ji)的(de)種有效(xiao)的(de)方法。
　　電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)(she)(she)備(bei)通過接(jie)(jie)地(di)裝置接(jie)(jie)地(di)后(hou)，使電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)(she)(she)備(bei)的電(dian)(dian)(dian)(dian)位(wei)接(jie)(jie)近地(di)電(dian)(dian)(dian)(dian)位(wei)。由于接(jie)(jie)地(di)電(dian)(dian)(dian)(dian)阻(zu)的存在(zai)，電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)(she)(she)備(bei)對地(di)電(dian)(dian)(dian)(dian)位(wei)總是(shi)存在(zai)的，電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)(she)(she)備(bei)的接(jie)(jie)地(di)電(dian)(dian)(dian)(dian)阻(zu)越(yue)(yue)大(da)，發生(sheng)故(gu)障時，電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)(she)(she)備(bei)的對地(di)電(dian)(dian)(dian)(dian)位(wei)也(ye)越(yue)(yue)大(da)，人觸(chu)及時的危(wei)險(xian)性也(ye)越(yue)(yue)大(da)。但是(shi)，如(ru)果不(bu)設(she)(she)(she)(she)置接(jie)(jie)地(di)裝置，故(gu)障設(she)(she)(she)(she)備(bei)外殼的電(dian)(dian)(dian)(dian)壓f就和相(xiang)線(xian)對地(di)電(dian)(dian)(dian)(dian)壓相(xiang)同，比(bi)起(qi)接(jie)(jie)地(di)電(dian)(dian)(dian)(dian)壓還是(shi)高(gao)出很多的，因(yin)此危(wei)險(xian)性也(ye)相(xiang)應增加。
　　2.2保(bao)*電(dian)(dian)(dian)力系統的正常運行。電(dian)(dian)(dian)力系統的接(jie)(jie)地，又(you)稱(cheng)工作接(jie)(jie)地，一(yi)般在變電(dian)(dian)(dian)站或變電(dian)(dian)(dian)所對中性點進行接(jie)(jie)地。工作接(jie)(jie)地的接(jie)(jie)地電(dian)(dian)(dian)阻(zu)要(yao)求(qiu)很(hen)小，對大型的變電(dian)(dian)(dian)站要(yao)求(qiu)有(you)一(yi)個(ge)接(jie)(jie)地網，保(bao)*接(jie)(jie)地電(dian)(dian)(dian)阻(zu)小而且可(ke)靠。工作接(jie)(jie)地的目的是使電(dian)(dian)(dian)網的中性點與地之間的電(dian)(dian)(dian)位接(jie)(jie)近于零。
　　2.3防止雷(lei)(lei)(lei)(lei)擊和(he)靜(jing)電的危害。雷(lei)(lei)(lei)(lei)電發生時，除了直接雷(lei)(lei)(lei)(lei)外，還會生產感(gan)應(ying)(ying)雷(lei)(lei)(lei)(lei)，感(gan)應(ying)(ying)雷(lei)(lei)(lei)(lei)又(you)分為靜(jing)電感(gan)應(ying)(ying)雷(lei)(lei)(lei)(lei)和(he)電磁感(gan)應(ying)(ying)雷(lei)(lei)(lei)(lei)。所有防雷(lei)(lei)(lei)(lei)措施(shi)中(zhong)最(zui)主要的方法是接地(di)。
　　3電(dian)氣設備(bei)接地技術原(yuan)則3.1為保*人身和設備(bei)安全，各種(zhong)電(dian)氣設備(bei)均(jun)應根(gen)據(ju)國家標(biao)準GB14050系(xi)統接地的形(xing)式及安全技術要(yao)求(qiu)進行保護(hu)(hu)接地。保護(hu)(hu)接地線(xian)除用以(yi)實現規定的工作接地或保護(hu)(hu)接地的要(yao)求(qiu)外(wai)，不應作其他(ta)用途。
　　3.2不同(tong)用(yong)途和不同(tong)電(dian)(dian)壓的電(dian)(dian)氣設(she)備，除(chu)有特殊(shu)要求外，一般應(ying)使用(yong)一個總(zong)的接(jie)地體，按等電(dian)(dian)位(wei)連接(jie)要求，應(ying)將建(jian)筑物金屬(shu)構件(jian)、金屬(shu)管道(dao)（輸送易燃易爆物的金屬(shu)管道(dao)除(chu)外）與總(zong)接(jie)地體相連接(jie)。
　　3.3人工總接(jie)(jie)地(di)(di)(di)體(ti)不宜(yi)設在建筑物內，總接(jie)(jie)地(di)(di)(di)體(ti)的接(jie)(jie)地(di)(di)(di)電(dian)阻(zu)應滿足各種接(jie)(jie)地(di)(di)(di)中最小(xiao)的接(jie)(jie)地(di)(di)(di)電(dian)阻(zu)要(yao)求。
　　3.4有特殊要求(qiu)的接地，如弱電系(xi)統、計(ji)算機系(xi)統及(ji)中壓系(xi)統，為中性(xing)點直(zhi)接接地或(huo)經小電阻接地時，應按(an)有關(guan)專項(xiang)規定執行。
　　4電(dian)(dian)(dian)(dian)(dian)氣(qi)設備接(jie)(jie)地方法安(an)全保(bao)(bao)護(hu)接(jie)(jie)地4.1.1保(bao)(bao)護(hu)接(jie)(jie)零(ling)(ling)。三(san)相四線(xian)(xian)(xian)(xian)制供電(dian)(dian)(dian)(dian)(dian)系統中的中性線(xian)(xian)(xian)(xian)，即為保(bao)(bao)護(hu)接(jie)(jie)零(ling)(ling)線(xian)(xian)(xian)(xian)，它是電(dian)(dian)(dian)(dian)(dian)路(lu)(lu)環路(lu)(lu)的重要組成部分。在(zai)中性點直接(jie)(jie)接(jie)(jie)地的三(san)相四線(xian)(xian)(xian)(xian)制電(dian)(dian)(dian)(dian)(dian)網中，電(dian)(dian)(dian)(dian)(dian)子電(dian)(dian)(dian)(dian)(dian)氣(qi)設備應保(bao)(bao)護(hu)接(jie)(jie)零(ling)(ling)。將(jiang)電(dian)(dian)(dian)(dian)(dian)子電(dian)(dian)(dian)(dian)(dian)氣(qi)設備正常運行時(shi)不帶電(dian)(dian)(dian)(dian)(dian)的金屬外殼與電(dian)(dian)(dian)(dian)(dian)網的零(ling)(ling)線(xian)(xian)(xian)(xian)連接(jie)(jie)起(qi)來，當相發(fa)生漏(lou)電(dian)(dian)(dian)(dian)(dian)或碰殼時(shi)，由(you)于金屬外殼與零(ling)(ling)線(xian)(xian)(xian)(xian)相連，形成單相短(duan)路(lu)(lu)，電(dian)(dian)(dian)(dian)(dian)流很(hen)大，使電(dian)(dian)(dian)(dian)(dian)路(lu)(lu)保(bao)(bao)護(hu)裝置迅(xun)速動作(zuo)，切斷電(dian)(dian)(dian)(dian)(dian)源。在(zai)采(cai)用(yong)接(jie)(jie)零(ling)(ling)保(bao)(bao)護(hu)時(shi)，電(dian)(dian)(dian)(dian)(dian)源中線(xian)(xian)(xian)(xian)不允(yun)許斷開(kai)，如(ru)果中線(xian)(xian)(xian)(xian)斷開(kai)，將(jiang)會(hui)失(shi)去保(bao)(bao)護(hu)作(zuo)用(yong)。通常系統中采(cai)用(yong)零(ling)(ling)線(xian)(xian)(xian)(xian)重復接(jie)(jie)地的方法實(shi)現保(bao)(bao)護(hu)作(zuo)用(yong)。
　　4.1.2保護(hu)(hu)接(jie)地。為(wei)防止觸電事(shi)故而(er)裝設的(de)接(jie)地，稱(cheng)之為(wei)保護(hu)(hu)接(jie)地。保護(hu)(hu)接(jie)地僅適用于中性(xing)點不(bu)接(jie)地的(de)電網。凡在這個電網中的(de)電氣設備(bei)的(de)金屬外殼、支架(jia)及相連的(de)金屬部分均應接(jie)地。中性(xing)點接(jie)地的(de)電路系統不(bu)宜(yi)采用保護(hu)(hu)接(jie)地。
　　系(xi)統(tong)接(jie)地線(xian)既是(shi)各(ge)電(dian)(dian)路(lu)中的(de)(de)(de)(de)靜態(tai)、動態(tai)電(dian)(dian)流通(tong)(tong)道，又是(shi)各(ge)級電(dian)(dian)路(lu)通(tong)(tong)過共(gong)同的(de)(de)(de)(de)接(jie)地阻(zu)抗而相互耦合的(de)(de)(de)(de)途徑，從(cong)而形成電(dian)(dian)路(lu)間相互千(qian)擾的(de)(de)(de)(de)薄弱環(huan)節。所以，電(dian)(dian)子(zi)電(dian)(dian)氣儀(yi)器(qi)設(she)備(bei)中的(de)(de)(de)(de)一切抗千(qian)擾技術，都和接(jie)地有關。電(dian)(dian)子(zi)電(dian)(dian)氣儀(yi)器(qi)設(she)備(bei)中的(de)(de)(de)(de)系(xi)統(tong)接(jie)地是(shi)否(fou)要接(jie)大(da)地和如何接(jie)大(da)地，與系(xi)統(tong)的(de)(de)(de)(de)工作穩定性有著(zhu)密切的(de)(de)(de)(de)關系(xi)，通(tong)(tong)常有4種方(fang)式。
　　4.2.1浮地(di)(di)方式。浮地(di)(di)就是(shi)不接(jie)大地(di)(di)，是(shi)一種懸浮的(de)(de)(de)方式，其目(mu)的(de)(de)(de)是(shi)將電(dian)(dian)路或設備與公共地(di)(di)或可能引起環流(liu)的(de)(de)(de)公共導線隔離開來，從而抑制來自接(jie)地(di)(di)線的(de)(de)(de)千擾。這種接(jie)地(di)(di)方式的(de)(de)(de)缺點是(shi)設備不與大地(di)(di)直接(jie)相連，容易出現(xian)靜(jing)電(dian)(dian)積(ji)累現(xian)象，這樣積(ji)累起來的(de)(de)(de)電(dian)(dian)荷達(da)到(dao)一定程度后，在設備和大地(di)(di)之間(jian)會產生(sheng)具有強大放電(dian)(dian)電(dian)(dian)流(liu)的(de)(de)(de)靜(jing)電(dian)(dian)擊穿現(xian)象，這是(shi)一種破(po)壞性很(hen)強的(de)(de)(de)千擾源(yuan)。
　　4.2.2單點接(jie)(jie)(jie)地(di)方式。由于2點接(jie)(jie)(jie)地(di)易(yi)形成接(jie)(jie)(jie)地(di)環路(lu)，所以點接(jie)(jie)(jie)地(di)的功能是(shi)消除和(he)防止形成接(jie)(jie)(jie)地(di)環路(lu)。單點接(jie)(jie)(jie)地(di)有串(chuan)聯和(he)并聯2種(zhong)方式。單點接(jie)(jie)(jie)地(di)是(shi)為許多接(jie)(jie)(jie)在一起的電路(lu)系統提(ti)供共同點。
　　電流流過(guo)接(jie)(jie)地導線時，導線中或多或少有阻(zu)抗(kang)。串(chuan)聯接(jie)(jie)地電路(lu)(lu)電流11，2IN都經過(guo)阻(zu)抗(kang)Z1，Z1是電路(lu)(lu)1，2N共有的共同阻(zu)抗(kang)，因此，電路(lu)(lu)1，2N的電位受11，2IN共同影響，它們之間互(hu)相(xiang)牽制。而并聯接(jie)(jie)地方式沒有公共阻(zu)抗(kang)，電路(lu)(lu)1，2N互(hu)不千擾，所(suo)以(yi)并聯接(jie)(jie)地最為簡單實用(yong)。
　　4.2.3多點接地(di)(di)方式(shi)。對(dui)于高(gao)頻(pin)(pin)電(dian)路(lu)（信號頻(pin)(pin)率為10MHz以(yi)上，由(you)于各(ge)元(yuan)器件(jian)的(de)(de)(de)(de)引線(xian)和(he)電(dian)路(lu)本(ben)身(shen)布局(ju)的(de)(de)(de)(de)電(dian)感都將(jiang)增(zeng)加接地(di)(di)線(xian)的(de)(de)(de)(de)阻(zu)抗，一點接地(di)(di)方式(shi)已不再適用(yong)。為了降(jiang)低(di)接地(di)(di)線(xian)阻(zu)抗及減(jian)少地(di)(di)線(xian)間的(de)(de)(de)(de)雜(za)散(san)電(dian)感和(he)分布電(dian)容所造成的(de)(de)(de)(de)電(dian)路(lu)間的(de)(de)(de)(de)相互耦合(he)，應短距(ju)離把(ba)各(ge)元(yuan)器件(jian)接地(di)(di)端子(zi)接在此地(di)(di)面(mian)上。
　　4.2.4混(hun)合接(jie)地(di)。電(dian)路系統(tong)既(ji)有(you)低頻電(dian)路，又有(you)高頻電(dian)路或(huo)數(shu)字電(dian)路時，在系統(tong)中應采(cai)用(yong)混(hun)合接(jie)地(di)方(fang)式(shi)(shi)。電(dian)路系統(tong)中的(de)(de)低頻部分采(cai)用(yong)單點(dian)(dian)接(jie)地(di)，而高頻部分則需要多(duo)點(dian)(dian)接(jie)地(di)，這樣(yang)的(de)(de)接(jie)地(di)方(fang)式(shi)(shi)既(ji)包(bao)含了單點(dian)(dian)接(jie)地(di)的(de)(de)特(te)性，又包(bao)含了多(duo)點(dian)(dian)接(jie)地(di)的(de)(de)特(te)性，從而達(da)到較佳抑制千(qian)擾的(de)(de)目的(de)(de)。