LED顯示屏是的主體元件是LED和驅動芯片,屬于微電子產品的集合體,LED的工作電壓在5V左右,一般工作電流為20毫安以下。它的工作特性決定了它面對靜電和異常電壓或電流沖擊的抗性十分脆弱。這就需要我們在生產和使用過程中認識到這一點并給予足夠的重視，采取措施對led顯示屏進行保護。而電源接地是LED顯示屏最常用的一種保護方法。下面河南電子屏廠家來跟大家探(tan)討一下吧(ba)！

為什么電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)要接地(di)(di)(di)？這個和(he)開關(guan)(guan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)的(de)(de)(de)(de)工作(zuo)(zuo)模式有關(guan)(guan)，我(wo)們(men)(men)LED顯(xian)示屏(ping)開關(guan)(guan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)是(shi)一(yi)(yi)種通(tong)過濾(lv)波—整(zheng)流(liu)(liu)(liu)—脈(mo)沖(chong)調制—輸出整(zheng)流(liu)(liu)(liu)—濾(lv)波等(deng)一(yi)(yi)系(xi)列(lie)手(shou)段將交流(liu)(liu)(liu)（AC）220V市電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)轉化成直流(liu)(liu)(liu)(DC)5V直流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)穩(wen)定輸出的(de)(de)(de)(de)一(yi)(yi)種設(she)備。為了保證電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)AC/DC轉化的(de)(de)(de)(de)穩(wen)定性(xing)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)廠家按照國家3C強制標準(zhun)在(zai)AC220V輸入端的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路設(she)計中，從火線至地(di)(di)(di)線跨接一(yi)(yi)個EMI濾(lv)波電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路。以(yi)保證AC220V輸入的(de)(de)(de)(de)穩(wen)定性(xing)，所以(yi)所有的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)在(zai)工作(zuo)(zuo)是(shi)都會存(cun)在(zai)濾(lv)波漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，單(dan)個電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)的(de)(de)(de)(de)漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)(de)(de)3.5mA左(zuo)右。漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)約為110V。在(zai)顯(xian)示屏(ping)不(bu)接地(di)(di)(di)的(de)(de)(de)(de)情況(kuang)下，漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)不(bu)但可能引起芯(xin)片(pian)損壞或者燈管燒(shao)壞。如(ru)果(guo)使用20個電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)以(yi)上，累加的(de)(de)(de)(de)漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)達(da)到70mA以(yi)上。足以(yi)導致漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)保護器動作(zuo)(zuo)，切斷供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。這個也是(shi)為什么我(wo)們(men)(men)顯(xian)示屏(ping)無法(fa)使用漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)保護器的(de)(de)(de)(de)原因。如(ru)果(guo)不(bu)接漏(lou)(lou)(lou)保而且顯(xian)示屏(ping)不(bu)接地(di)(di)(di)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)疊加的(de)(de)(de)(de)漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)將超過人體安全電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)，110V的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)足以(yi)致人死地(di)(di)(di)！而接地(di)(di)(di)后，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)外殼電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)對人體接近0。表明(ming)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)與(yu)人體之間不(bu)存(cun)在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)位差，漏(lou)(lou)(lou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)被導入大(da)地(di)(di)(di)。所以(yi),LED顯(xian)示屏(ping)必須接地(di)(di)(di)。

但是經(jing)常(chang)有(you)客(ke)戶采用錯誤的接(jie)地方法(fa)為顯(xian)示屏接(jie)地，常(chang)見(jian)的有(you)：

1、認為(wei)戶(hu)外立柱(zhu)式結構的(de)立柱(zhu)下端(duan)是與大地連接，所以不需要在做顯示屏(ping)接地；

2、認為電(dian)源是鎖在箱體上，而箱體之(zhi)間是相互用鎖扣與結構(gou)連接(jie)，所以結構(gou)接(jie)地(di)就代表電(dian)源也接(jie)地(di)。

此兩類做法存在誤(wu)區(qu)，我們的(de)(de)(de)(de)立柱(zhu)是與地(di)基的(de)(de)(de)(de)地(di)腳螺(luo)栓保持連接，而(er)地(di)腳螺(luo)栓是預(yu)埋在混凝土(tu)里(li)面的(de)(de)(de)(de)，混凝土(tu)的(de)(de)(de)(de)電阻在100-500Ω的(de)(de)(de)(de)范圍內，接地(di)電阻過高(gao)將導(dao)(dao)致(zhi)(zhi)漏(lou)電流泄(xie)放不(bu)及時或存在殘留。我們的(de)(de)(de)(de)箱體(ti)(ti)(ti)表面有(you)(you)噴(pen)涂油(you)漆(qi)(qi)，而(er)油(you)漆(qi)(qi)是電的(de)(de)(de)(de)不(bu)良導(dao)(dao)體(ti)(ti)(ti)，將會導(dao)(dao)致(zhi)(zhi)箱體(ti)(ti)(ti)連接接地(di)的(de)(de)(de)(de)接觸(chu)不(bu)良或接地(di)電阻升高(gao)，有(you)(you)可能出(chu)現(xian)電火花干擾(rao)屏體(ti)(ti)(ti)信(xin)號。隨著(zhu)時間的(de)(de)(de)(de)推移(yi)，箱體(ti)(ti)(ti)或結(jie)構表面將會出(chu)現(xian)氧(yang)化(hua)(hua)和銹蝕，螺(luo)絲等固定(ding)件也隨著(zhu)溫差變化(hua)(hua)導(dao)(dao)致(zhi)(zhi)的(de)(de)(de)(de)熱脹冷(leng)縮逐漸松動。將會導(dao)(dao)致(zhi)(zhi)結(jie)構接地(di)的(de)(de)(de)(de)效果減弱甚至(zhi)完全失(shi)效。形成安(an)全隱患。導(dao)(dao)致(zhi)(zhi)漏(lou)流觸(chu)電、芯片受干擾(rao)損壞等安(an)全事故(gu)的(de)(de)(de)(de)發(fa)生。

那(nei)么，標準的接(jie)地應(ying)該是(shi)怎樣(yang)的呢？如下所示(shi)：電(dian)源(yuan)輸入端(duan)有3個接(jie)線(xian)(xian)端(duan)子(zi)(zi)(zi)，分(fen)別是(shi)火線(xian)(xian)端(duan)子(zi)(zi)(zi)、零線(xian)(xian)端(duan)子(zi)(zi)(zi)和接(jie)地端(duan)子(zi)(zi)(zi)。正確(que)的接(jie)地做法是(shi)使用(yong)接(jie)地專(zhuan)用(yong)的黃綠雙色線(xian)(xian)將所有電(dian)源(yuan)地線(xian)(xian)端(duan)子(zi)(zi)(zi)串接(jie)并鎖緊，然(ran)后引出(chu)連接(jie)至接(jie)地端(duan)。

如(ru)果現(xian)場(chang)沒有(you)接(jie)(jie)(jie)地(di)(di)(di)(di)端子(zi)，可以連(lian)接(jie)(jie)(jie)至鐵質自(zi)來(lai)水管或鐵質下(xia)水管道等埋(mai)設與大(da)地(di)(di)(di)(di)并與大(da)地(di)(di)(di)(di)保持良好(hao)接(jie)(jie)(jie)觸的管道上，為保證接(jie)(jie)(jie)觸良好(hao)應(ying)在此類自(zi)然接(jie)(jie)(jie)地(di)(di)(di)(di)體上焊(han)接(jie)(jie)(jie)接(jie)(jie)(jie)線(xian)端子(zi)，然后將地(di)(di)(di)(di)線(xian)緊鎖在接(jie)(jie)(jie)線(xian)端子(zi)上，不得捆(kun)綁連(lian)接(jie)(jie)(jie)。但(dan)煤氣(qi)等易燃易爆和的管道不得使用。或者現(xian)場(chang)埋(mai)設接(jie)(jie)(jie)地(di)(di)(di)(di)體。接(jie)(jie)(jie)地(di)(di)(di)(di)體可以采用角鋼(gang)或者鋼(gang)管，水平或者豎直埋(mai)入大(da)地(di)(di)(di)(di)中作為簡易接(jie)(jie)(jie)地(di)(di)(di)(di)點，接(jie)(jie)(jie)地(di)(di)(di)(di)點應(ying)選擇偏僻的地(di)(di)(di)(di)方(fang)，以免行(xing)人(ren)或者車輛(liang)破壞(huai)接(jie)(jie)(jie)地(di)(di)(di)(di)體。

我(wo)們接(jie)(jie)地(di)時(shi)(shi)接(jie)(jie)地(di)電(dian)(dian)阻(zu)必須小于4歐(ou)姆，以保證漏電(dian)(dian)流(liu)的(de)及時(shi)(shi)泄放(fang)。需(xu)要注意的(de)是，防雷(lei)(lei)(lei)接(jie)(jie)地(di)端(duan)在(zai)泄放(fang)雷(lei)(lei)(lei)擊電(dian)(dian)流(liu)時(shi)(shi)由于大(da)地(di)電(dian)(dian)流(liu)的(de)擴散需(xu)要一定時(shi)(shi)間(jian)，短(duan)時(shi)(shi)間(jian)內會導(dao)致大(da)地(di)電(dian)(dian)位升高(gao)，如果(guo)LED顯(xian)示(shi)(shi)屏接(jie)(jie)地(di)聯(lian)接(jie)(jie)至(zhi)防雷(lei)(lei)(lei)接(jie)(jie)地(di)端(duan)，這(zhe)時(shi)(shi)大(da)地(di)電(dian)(dian)位比顯(xian)示(shi)(shi)屏要高(gao)，雷(lei)(lei)(lei)擊電(dian)(dian)流(liu)將(jiang)會沿順這(zhe)地(di)線傳遞至(zhi)屏體，造成設(she)備損(sun)壞。所(suo)以LED顯(xian)示(shi)(shi)屏這(zhe)種保護接(jie)(jie)地(di)不(bu)得聯(lian)結(jie)至(zhi)防雷(lei)(lei)(lei)接(jie)(jie)地(di)端(duan)上，保護接(jie)(jie)地(di)端(duan)必須距離防雷(lei)(lei)(lei)接(jie)(jie)地(di)端(duan)20米以上。防止地(di)電(dian)(dian)位的(de)反擊。

LED接地注(zhu)意事項總(zong)結：

1、每個電(dian)源都必須從接地端子接地，并鎖緊；

2、接地電阻不得大于4Ω；

3、地線應為專屬導線，嚴禁(jin)和零線聯(lian)接；

4、地線(xian)上不(bu)得(de)安裝空開(kai)或熔斷器(qi)；

5、地(di)線和接地(di)端(duan)子都應遠離(li)防雷接地(di)端(duan)20以上；

嚴(yan)禁部(bu)分設(she)備采用(yong)保(bao)護(hu)接(jie)(jie)地(di)來代(dai)替(ti)保(bao)護(hu)接(jie)(jie)零(ling)，造成保(bao)護(hu)接(jie)(jie)地(di)和保(bao)護(hu)接(jie)(jie)零(ling)混接(jie)(jie)錯(cuo)接(jie)(jie)。當某(mou)一(yi)保(bao)護(hu)接(jie)(jie)地(di)設(she)備的(de)絕(jue)緣(yuan)損壞，發生相線(xian)碰殼(ke)時，零(ling)線(xian)出(chu)現對地(di)電壓，于是使保(bao)護(hu)接(jie)(jie)零(ling)設(she)備的(de)外殼(ke)上就產生了危險電壓。

因此，在同(tong)一(yi)(yi)母(mu)線供電(dian)(dian)的線路(lu)中，保(bao)護(hu)接(jie)地和保(bao)護(hu)接(jie)零(ling)不能混用(yong)(yong)，即不可把一(yi)(yi)部(bu)分電(dian)(dian)氣設(she)備(bei)接(jie)零(ling)，而將(jiang)另一(yi)(yi)部(bu)分電(dian)(dian)氣設(she)備(bei)接(jie)地。一(yi)(yi)般市電(dian)(dian)都采用(yong)(yong)接(jie)零(ling)保(bao)護(hu)，故使用(yong)(yong)市電(dian)(dian)的電(dian)(dian)氣設(she)備(bei)，應采取接(jie)零(ling)保(bao)護(hu)。

4、保護接(jie)零注意(yi)事項

（1）在(zai)保(bao)護(hu)(hu)接零(ling)的電(dian)(dian)氣系統中。零(ling)線起著至關重(zhong)要的作用。一旦零(ling)線斷(duan)(duan)(duan)(duan)開，接在(zai)斷(duan)(duan)(duan)(duan)線處后(hou)面(mian)的一段線路的電(dian)(dian)氣設(she)(she)備(bei)相當于沒有了(le)保(bao)護(hu)(hu)接零(ling)和保(bao)護(hu)(hu)接地，若在(zai)零(ling)線斷(duan)(duan)(duan)(duan)處后(hou)面(mian)有電(dian)(dian)氣設(she)(she)備(bei)外(wai)殼(ke)(ke)漏電(dian)(dian)則不(bu)構成短路回路，而使(shi)熔(rong)體(ti)熔(rong)斷(duan)(duan)(duan)(duan)。不(bu)但該臺(tai)設(she)(she)備(bei)外(wai)殼(ke)(ke)帶有電(dian)(dian)壓，而且(qie)使(shi)得斷(duan)(duan)(duan)(duan)線處后(hou)面(mian)的所有設(she)(she)備(bei)的外(wai)殼(ke)(ke)都存在(zai)接近電(dian)(dian)源相電(dian)(dian)壓的對地電(dian)(dian)壓，觸電(dian)(dian)危(wei)險性將擴大。

所(suo)有電氣(qi)設備接保護接零(ling)(ling)線(xian)(xian)(xian)均(jun)應(ying)以并聯方式接在電源零(ling)(ling)線(xian)(xian)(xian)上(shang)，不允許(xu)串聯，并用螺栓壓緊(jin)，牢固可靠，接觸良好。在零(ling)(ling)線(xian)(xian)(xian)上(shang)，禁止安裝保險和單獨(du)開關。在特殊(shu)的環境中，零(ling)(ling)線(xian)(xian)(xian)做防腐處理也(ye)就(jiu)不言(yan)而(er)喻了。

（2）中(zhong)(zhong)性(xing)點不接(jie)(jie)地(di)的(de)(de)三相四線(xian)制配電(dian)系統中(zhong)(zhong)，不允許用(yong)(yong)保護接(jie)(jie)零(ling)(ling)，只能用(yong)(yong)保護接(jie)(jie)地(di)。系統中(zhong)(zhong)任(ren)意一相發生(sheng)接(jie)(jie)地(di)，整個系統仍照常運行(xing)，但(dan)大地(di)與接(jie)(jie)地(di)線(xian)等(deng)電(dian)位(wei)，則接(jie)(jie)在零(ling)(ling)線(xian)上的(de)(de)用(yong)(yong)電(dian)設(she)備外(wai)殼對地(di)電(dian)壓(ya)降(jiang)等(deng)于接(jie)(jie)地(di)的(de)(de)相線(xian)從(cong)接(jie)(jie)地(di)點到中(zhong)(zhong)性(xing)點的(de)(de)電(dian)壓(ya)值，是十分(fen)危險的(de)(de)。

（3）在采用(yong)保護接(jie)零系(xi)統中(zhong)還要在電源(yuan)中(zhong)性(xing)(xing)點進(jin)行工作(zuo)接(jie)地(di)和(he)零線(xian)一定(ding)間隔距離及(ji)終端進(jin)行重(zhong)復接(jie)地(di)。在中(zhong)性(xing)(xing)點接(jie)地(di)的系(xi)統中(zhong)除將變壓器中(zhong)性(xing)(xing)點做接(jie)地(di)外，沿零線(xian)走向的一處或者多(duo)處再次將零線(xian)接(jie)地(di)叫(jiao)重(zhong)復接(jie)地(di)。

其作用(yong)是(shi)當電(dian)(dian)(dian)氣(qi)設(she)備外(wai)殼漏電(dian)(dian)(dian)時(shi)可以降低對地電(dian)(dian)(dian)壓(ya)。當零線(xian)斷(duan)(duan)時(shi)也減(jian)輕觸電(dian)(dian)(dian)危(wei)險。當電(dian)(dian)(dian)氣(qi)設(she)備外(wai)殼漏電(dian)(dian)(dian)時(shi)，經相線(xian)、零線(xian)構成短(duan)路(lu)回路(lu)，短(duan)路(lu)電(dian)(dian)(dian)流將熔(rong)斷(duan)(duan)保險。設(she)備外(wai)殼隨之(zhi)斷(duan)(duan)電(dian)(dian)(dian)，不會出現觸電(dian)(dian)(dian)危(wei)險。但是(shi)保險熔(rong)斷(duan)(duan)之(zhi)前設(she)備帶(dai)(dai)電(dian)(dian)(dian)，對人身還是(shi)有危(wei)險的(de)。若在接近設(she)備處再加(jia)接地裝置，即實行重(zhong)復接地，帶(dai)(dai)電(dian)(dian)(dian)設(she)備的(de)導體部分(fen)對地電(dian)(dian)(dian)壓(ya)降低。

（4）保(bao)護(hu)接零必須(xu)有可靠靈(ling)敏(min)的(de)短路保(bao)護(hu)裝置來配合，因此，熔(rong)斷(duan)絲嚴禁(jin)用銅絲等(deng)金(jin)屬材料來代替符合要求的(de)金(jin)屬熔(rong)斷(duan)絲，否則接零保(bao)護(hu)將失(shi)去其(qi)保(bao)護(hu)作用。

以(yi)上都是(shi)河南電(dian)子屏廠家為大家講解的相關內容，希望可以(yi)幫助(zhu)到(dao)大家！