點擊數：22452013-05-02 10:07:25 來源: 汕頭市鐘金達電氣設備有限公司-梅蘭日蘭、施耐德、常熟、指明集團專業供應商、汕頭成套設備廠
為了達(da)到安(an)全(quan)(quan)用電(dian)(dian)的目的，必須(xu)(xu)采用可靠的技術(shu)措(cuo)施(shi)，防止(zhi)觸(chu)(chu)電(dian)(dian)事故發生。絕緣、安(an)全(quan)(quan)間(jian)距、漏電(dian)(dian)保(bao)護(hu)、安(an)全(quan)(quan)電(dian)(dian)壓、遮(zhe)欄及(ji)阻(zu)擋物等都是(shi)防止(zhi)直接觸(chu)(chu)電(dian)(dian)的防護(hu)措(cuo)施(shi)。保(bao)護(hu)接地、保(bao)護(hu)接零是(shi)間(jian)接觸(chu)(chu)電(dian)(dian)防護(hu)措(cuo)施(shi)中最基本的措(cuo)施(shi)。所謂(wei)間(jian)接觸(chu)(chu)電(dian)(dian)防護(hu)措(cuo)施(shi)是(shi)指防止(zhi)人體(ti)各個(ge)部位觸(chu)(chu)及(ji)正常情況下(xia)不帶(dai)電(dian)(dian)，而在(zai)故障情況下(xia)才(cai)變為帶(dai)電(dian)(dian)的電(dian)(dian)器金屬部分(fen)的技術(shu)措(cuo)施(shi)。 專(zhuan)業電(dian)(dian)工(gong)(gong)人員(yuan)在(zai)全(quan)(quan)部停(ting)電(dian)(dian)或部分(fen)停(ting)電(dian)(dian)的電(dian)(dian)氣設(she)備上(shang)工(gong)(gong)作時，在(zai)技術(shu)措(cuo)施(shi)上(shang)，必須(xu)(xu)完成停(ting)電(dian)(dian)、驗電(dian)(dian)、裝(zhuang)設(she)接地線(xian)、懸掛標示牌和裝(zhuang)設(she)遮(zhe)欄后，才(cai)能(neng)開始(shi)工(gong)(gong)作。
一、絕緣
1.絕(jue)(jue)緣(yuan)(yuan)(yuan)的(de)作(zuo)用(yong) 絕(jue)(jue)緣(yuan)(yuan)(yuan)是用(yong)絕(jue)(jue)緣(yuan)(yuan)(yuan)材(cai)料(liao)把帶電(dian)(dian)體(ti)(ti)隔離(li)起來，實現帶電(dian)(dian)體(ti)(ti)之間、帶電(dian)(dian)體(ti)(ti)與其他物(wu)體(ti)(ti)之間的(de)電(dian)(dian)氣隔離(li)，使設(she)(she)備能長期安全、正(zheng)常(chang)地工(gong)作(zuo)，同時(shi)可(ke)以防(fang)(fang)止(zhi)人體(ti)(ti)觸(chu)及(ji)帶電(dian)(dian)部(bu)分(fen)，避免發生觸(chu)電(dian)(dian)事故(gu)，所以絕(jue)(jue)緣(yuan)(yuan)(yuan)在(zai)電(dian)(dian)氣安全中有著十分(fen)重(zhong)要(yao)的(de)作(zuo)用(yong)。良(liang)好的(de)絕(jue)(jue)緣(yuan)(yuan)(yuan)是設(she)(she)備和(he)線路正(zheng)常(chang)運行的(de)必要(yao)條件，也是防(fang)(fang)止(zhi)觸(chu)電(dian)(dian)事故(gu)的(de)重(zhong)要(yao)措施。 絕(jue)(jue)緣(yuan)(yuan)(yuan)具有很強隔電(dian)(dian)能力，被廣泛地應用(yong)在(zai)許(xu)多電(dian)(dian)器、電(dian)(dian)氣設(she)(she)備、裝置及(ji)電(dian)(dian)氣工(gong)程上，如膠木、塑料(liao)、橡膠、云(yun)母及(ji)礦(kuang)物(wu)油(you)等都(dou)是常(chang)用(yong)的(de)絕(jue)(jue)緣(yuan)(yuan)(yuan)材(cai)料(liao)。
2.絕(jue)(jue)緣(yuan)破壞(huai)(huai)(huai) 絕(jue)(jue)緣(yuan)材料(liao)經(jing)過(guo)一段時(shi)(shi)(shi)間的使(shi)用會(hui)(hui)發生(sheng)絕(jue)(jue)緣(yuan)破壞(huai)(huai)(huai)。絕(jue)(jue)緣(yuan)材料(liao)除因在(zai)強電(dian)(dian)(dian)場(chang)作用下(xia)被擊穿(chuan)而(er)破壞(huai)(huai)(huai)外，自(zi)然老(lao)化、電(dian)(dian)(dian)化學(xue)擊穿(chuan)、機械損傷、潮濕、腐蝕、熱老(lao)化等也(ye)會(hui)(hui)降低其絕(jue)(jue)緣(yuan)性(xing)(xing)能(neng)或導(dao)致絕(jue)(jue)緣(yuan)破壞(huai)(huai)(huai)。 絕(jue)(jue)緣(yuan)體(ti)承受的電(dian)(dian)(dian)壓(ya)超過(guo)一定(ding)數(shu)值時(shi)(shi)(shi)，電(dian)(dian)(dian)流穿(chuan)過(guo)絕(jue)(jue)緣(yuan)體(ti)而(er)發生(sheng)放(fang)電(dian)(dian)(dian)現象(xiang)稱為電(dian)(dian)(dian)擊穿(chuan)。 氣體(ti)絕(jue)(jue)緣(yuan)在(zai)擊穿(chuan)電(dian)(dian)(dian)壓(ya)消失后(hou)，絕(jue)(jue)緣(yuan)性(xing)(xing)能(neng)還能(neng)恢(hui)復;液體(ti)絕(jue)(jue)緣(yuan)多次擊穿(chuan)后(hou)，將嚴(yan)重(zhong)降低絕(jue)(jue)緣(yuan)性(xing)(xing)能(neng);而(er)固體(ti)絕(jue)(jue)緣(yuan)擊穿(chuan)后(hou)，就不能(neng)再恢(hui)復絕(jue)(jue)緣(yuan)性(xing)(xing)能(neng)。 在(zai)長時(shi)(shi)(shi)間存在(zai)電(dian)(dian)(dian)壓(ya)的情況(kuang)下(xia)，由于(yu)絕(jue)(jue)緣(yuan)材料(liao)的自(zi)然老(lao)化、電(dian)(dian)(dian)化學(xue)作用、熱效應作用，使(shi)其絕(jue)(jue)緣(yuan)性(xing)(xing)能(neng)逐漸(jian)降低，有(you)時(shi)(shi)(shi)電(dian)(dian)(dian)壓(ya)并不是很高也(ye)會(hui)(hui)造成電(dian)(dian)(dian)擊穿(chuan)。所以絕(jue)(jue)緣(yuan)需定(ding)期(qi)檢測，保證(zheng)電(dian)(dian)(dian)氣絕(jue)(jue)緣(yuan)的安全可(ke)靠。
3.絕緣安全用具
一些(xie)情(qing)況下，手(shou)(shou)(shou)持電(dian)動工(gong)具(ju)(ju)(ju)的(de)操作(zuo)者必(bi)(bi)須戴絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)手(shou)(shou)(shou)套、穿(chuan)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)鞋(xie)(靴(xue)(xue))，或站在(zai)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)墊(臺(tai))上工(gong)作(zuo)，采用(yong)(yong)(yong)(yong)這些(xie)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)使(shi)人(ren)與(yu)地面，或使(shi)人(ren)與(yu)工(gong)具(ju)(ju)(ju)的(de)金(jin)屬外殼，其中包括與(yu)相連的(de)金(jin)屬導體(ti)，隔離開來。這是目前簡便可行(xing)的(de)安全(quan)措施(shi)。 為了防止(zhi)機械(xie)傷害(hai)，使(shi)用(yong)(yong)(yong)(yong)手(shou)(shou)(shou)電(dian)鉆時不允許戴線手(shou)(shou)(shou)套。絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)應按有關規定(ding)進行(xing)定(ding)期耐壓(ya)(ya)試驗(yan)和(he)外觀檢查(cha)，凡是不合(he)格的(de)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)嚴禁使(shi)用(yong)(yong)(yong)(yong)，絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)應由專人(ren)負責保管和(he)檢查(cha)。 常用(yong)(yong)(yong)(yong)的(de)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)有絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)手(shou)(shou)(shou)套、絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)靴(xue)(xue)、絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)鞋(xie)、絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)墊和(he)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)臺(tai)等。絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)可分(fen)為基(ji)本(ben)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)和(he)輔助(zhu)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)。基(ji)本(ben)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)的(de)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)強度能長時間(jian)承(cheng)受電(dian)氣設(she)備的(de)工(gong)作(zuo)電(dian)壓(ya)(ya)，使(shi)用(yong)(yong)(yong)(yong)時，可直接接觸電(dian)氣設(she)備的(de)有電(dian)部分(fen)。輔助(zhu)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)的(de)絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)強度不足以承(cheng)受電(dian)氣設(she)備的(de)工(gong)作(zuo)電(dian)壓(ya)(ya)，只能加強基(ji)本(ben)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)的(de)保安作(zuo)用(yong)(yong)(yong)(yong)，必(bi)(bi)須與(yu)基(ji)本(ben)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)一起使(shi)用(yong)(yong)(yong)(yong)。在(zai)低壓(ya)(ya)帶電(dian)設(she)備上工(gong)作(zuo)時，絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)手(shou)(shou)(shou)套、絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)鞋(xie)(靴(xue)(xue))、絕(jue)(jue)(jue)(jue)緣(yuan)(yuan)(yuan)(yuan)墊可作(zuo)為基(ji)本(ben)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)使(shi)用(yong)(yong)(yong)(yong)，在(zai)高壓(ya)(ya)情(qing)況下，只能用(yong)(yong)(yong)(yong)作(zuo)輔助(zhu)安全(quan)用(yong)(yong)(yong)(yong)具(ju)(ju)(ju)。
二、屏護
屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)是指采用(yong)遮欄、圍欄、護(hu)(hu)(hu)(hu)罩、護(hu)(hu)(hu)(hu)蓋(gai)或隔(ge)離板等(deng)把(ba)帶電(dian)體同外(wai)界(jie)隔(ge)絕開來，以防止(zhi)人體觸(chu)及或接(jie)近帶電(dian)體所采取的(de)(de)一種(zhong)安全技術措施。除防止(zhi)觸(chu)電(dian)的(de)(de)作用(yong)外(wai)，有(you)的(de)(de)屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)裝(zhuang)置(zhi)還能起到防止(zhi)電(dian)弧(hu)傷人、防止(zhi)弧(hu)光短路或便利檢修工作等(deng)作用(yong)。配電(dian)線路和電(dian)氣設備的(de)(de)帶電(dian)部分，如果不(bu)(bu)便加(jia)(jia)包絕緣或絕緣強度不(bu)(bu)足(zu)時，就可以采用(yong)屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)措施。 開關(guan)電(dian)器的(de)(de)可動部分一般(ban)不(bu)(bu)能加(jia)(jia)包絕緣，而(er)需(xu)要屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)。其(qi)中防護(hu)(hu)(hu)(hu)式(shi)開關(guan)電(dian)器本(ben)身帶有(you)屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)裝(zhuang)置(zhi)，如膠蓋(gai)閘刀開關(guan)的(de)(de)膠蓋(gai)、鐵殼開關(guan)的(de)(de)鐵殼等(deng);開啟式(shi)石板閘刀開關(guan)需(xu)要另加(jia)(jia)屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)裝(zhuang)置(zhi)。起重機(ji)滑觸(chu)線以及其(qi)他(ta)裸露的(de)(de)導線也需(xu)另加(jia)(jia)屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)裝(zhuang)置(zhi)。對于高壓設備，由于全部加(jia)(jia)絕緣往往有(you)困難，而(er)且(qie)當(dang)人接(jie)近至一定(ding)程度時，即會(hui)發生嚴重的(de)(de)觸(chu)電(dian)事故。因(yin)此，不(bu)(bu)論高壓設備是否已加(jia)(jia)絕緣，都要采取屏(ping)(ping)(ping)護(hu)(hu)(hu)(hu)或其(qi)他(ta)防止(zhi)接(jie)近的(de)(de)措施。
變配電(dian)(dian)(dian)(dian)(dian)設(she)備，凡安裝(zhuang)(zhuang)(zhuang)(zhuang)在(zai)(zai)室外地面上(shang)(shang)的(de)(de)(de)(de)(de)變壓(ya)器以及(ji)安裝(zhuang)(zhuang)(zhuang)(zhuang)在(zai)(zai)車(che)(che)間(jian)或(huo)(huo)公共場所(suo)的(de)(de)(de)(de)(de)變配電(dian)(dian)(dian)(dian)(dian)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，都需(xu)要(yao)設(she)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)遮(zhe)欄(lan)或(huo)(huo)柵欄(lan)作為屏(ping)(ping)護(hu)(hu)(hu)。鄰近帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)的(de)(de)(de)(de)(de)作業中，在(zai)(zai)工(gong)作人(ren)(ren)員(yuan)與帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)之間(jian)及(ji)過道、人(ren)(ren)口(kou)等(deng)處應(ying)(ying)裝(zhuang)(zhuang)(zhuang)(zhuang)設(she)可移(yi)動(dong)(dong)(dong)的(de)(de)(de)(de)(de)臨時遮(zhe)欄(lan)。 屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)不直接(jie)(jie)與帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)接(jie)(jie)觸，對(dui)(dui)所(suo)用(yong)(yong)材(cai)料的(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)性(xing)能沒有(you)(you)嚴格要(yao)求。屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)所(suo)用(yong)(yong)材(cai)料應(ying)(ying)當有(you)(you)足夠的(de)(de)(de)(de)(de)機械強度和良好的(de)(de)(de)(de)(de)耐(nai)火性(xing)能。但是金屬材(cai)料制成的(de)(de)(de)(de)(de)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，為了防(fang)止其意外帶(dai)電(dian)(dian)(dian)(dian)(dian)造成觸電(dian)(dian)(dian)(dian)(dian)事(shi)故，必(bi)須將其接(jie)(jie)地或(huo)(huo)接(jie)(jie)零(ling)。 屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)(de)(de)種類(lei)，有(you)(you)永久性(xing)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，如(ru)配電(dian)(dian)(dian)(dian)(dian)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)(de)(de)遮(zhe)欄(lan)、開關(guan)的(de)(de)(de)(de)(de)罩(zhao)蓋等(deng);臨時性(xing)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，如(ru)檢修工(gong)作中使用(yong)(yong)的(de)(de)(de)(de)(de)臨時屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)和臨時設(she)備的(de)(de)(de)(de)(de)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi);固定(ding)(ding)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，如(ru)母線的(de)(de)(de)(de)(de)護(hu)(hu)(hu)網(wang);移(yi)動(dong)(dong)(dong)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，如(ru)跟隨(sui)天車(che)(che)移(yi)動(dong)(dong)(dong)的(de)(de)(de)(de)(de)天車(che)(che)滑線的(de)(de)(de)(de)(de)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)等(deng)。 使用(yong)(yong)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)時，還(huan)應(ying)(ying)注意以下內容： (1)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)應(ying)(ying)與帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)之間(jian)保持足夠的(de)(de)(de)(de)(de)安全(quan)距離。 (2)被(bei)屏(ping)(ping)護(hu)(hu)(hu)的(de)(de)(de)(de)(de)帶(dai)電(dian)(dian)(dian)(dian)(dian)部分應(ying)(ying)有(you)(you)明(ming)顯(xian)標(biao)(biao)志，標(biao)(biao)明(ming)規定(ding)(ding)的(de)(de)(de)(de)(de)符號或(huo)(huo)涂上(shang)(shang)規定(ding)(ding)的(de)(de)(de)(de)(de)顏(yan)色。 遮(zhe)欄(lan)、柵欄(lan)等(deng)屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)上(shang)(shang)應(ying)(ying)有(you)(you)明(ming)顯(xian)的(de)(de)(de)(de)(de)標(biao)(biao)志，如(ru)根據(ju)被(bei)屏(ping)(ping)護(hu)(hu)(hu)對(dui)(dui)象掛上(shang)(shang)“止步，高壓(ya)危險!”、“禁止攀登，高壓(ya)危險!”等(deng)標(biao)(biao)示牌(pai)，必(bi)要(yao)時還(huan)應(ying)(ying)上(shang)(shang)鎖。標(biao)(biao)示牌(pai)只應(ying)(ying)由擔負安全(quan)責任的(de)(de)(de)(de)(de)人(ren)(ren)員(yuan)進行布(bu)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)和撤除。 (3)遮(zhe)欄(lan)出人(ren)(ren)口(kou)的(de)(de)(de)(de)(de)門(men)上(shang)(shang)應(ying)(ying)根據(ju)需(xu)要(yao)裝(zhuang)(zhuang)(zhuang)(zhuang)鎖，或(huo)(huo)采用(yong)(yong)信號裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)、聯鎖裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)。前者(zhe)一般是用(yong)(yong)燈(deng)光(guang)或(huo)(huo)儀表指(zhi)示有(you)(you)電(dian)(dian)(dian)(dian)(dian);后者(zhe)是采用(yong)(yong)專門(men)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)，當人(ren)(ren)體(ti)(ti)超過屏(ping)(ping)護(hu)(hu)(hu)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)而可能接(jie)(jie)近帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)時，被(bei)屏(ping)(ping)護(hu)(hu)(hu)的(de)(de)(de)(de)(de)帶(dai)電(dian)(dian)(dian)(dian)(dian)體(ti)(ti)將會自動(dong)(dong)(dong)斷電(dian)(dian)(dian)(dian)(dian)。
三、漏電保(bao)護器(qi)
漏(lou)電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)護(hu)(hu)器(qi)(qi)(qi)是(shi)一種在規定條件下(xia)電(dian)(dian)(dian)(dian)(dian)路中漏(lou)(觸)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(mA)值(zhi)(zhi)達到或(huo)(huo)超過(guo)其規定值(zhi)(zhi)時(shi)(shi)能(neng)(neng)自動(dong)斷開電(dian)(dian)(dian)(dian)(dian)路或(huo)(huo)發出報警的裝置。 漏(lou)電(dian)(dian)(dian)(dian)(dian)是(shi)指電(dian)(dian)(dian)(dian)(dian)器(qi)(qi)(qi)絕緣損壞(huai)或(huo)(huo)其他原因造(zao)成(cheng)(cheng)導電(dian)(dian)(dian)(dian)(dian)部分碰殼(ke)時(shi)(shi)，如(ru)果電(dian)(dian)(dian)(dian)(dian)器(qi)(qi)(qi)的金屬(shu)外(wai)(wai)殼(ke)是(shi)接地的，那(nei)么電(dian)(dian)(dian)(dian)(dian)就由(you)電(dian)(dian)(dian)(dian)(dian)器(qi)(qi)(qi)的金屬(shu)外(wai)(wai)殼(ke)經大地構成(cheng)(cheng)通路，從而形成(cheng)(cheng)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，即漏(lou)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，也叫(jiao)做接地電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)。當漏(lou)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)超過(guo)允許值(zhi)(zhi)時(shi)(shi)，漏(lou)電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)護(hu)(hu)器(qi)(qi)(qi)能(neng)(neng)夠自動(dong)切斷電(dian)(dian)(dian)(dian)(dian)源或(huo)(huo)報警，以保(bao)(bao)(bao)證人身(shen)安(an)全(quan)。 漏(lou)電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)護(hu)(hu)器(qi)(qi)(qi)動(dong)作(zuo)靈敏，切斷電(dian)(dian)(dian)(dian)(dian)源時(shi)(shi)間(jian)短，因此只要能(neng)(neng)夠合理選用和正確安(an)裝、使用漏(lou)電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)護(hu)(hu)器(qi)(qi)(qi)，除了保(bao)(bao)(bao)護(hu)(hu)人身(shen)安(an)全(quan)以外(wai)(wai)，還有防止(zhi)電(dian)(dian)(dian)(dian)(dian)氣設備損壞(huai)及預(yu)防火災的作(zuo)用。
必須安裝漏電(dian)保護器的設(she)備和場所：
(1)屬于I類的移動(dong)式電(dian)氣設備及手持式電(dian)氣工具;
(2)安裝在(zai)潮濕、強腐蝕性(xing)等惡(e)劣環境場所(suo)的電器(qi)設備(bei);
(3)建筑(zhu)施工(gong)工(gong)地的電氣施工(gong)機(ji)(ji)械設備(bei)，如打(da)樁機(ji)(ji)、攪拌機(ji)(ji)等;
(4)臨時(shi)用(yong)電的電器設備;
(5)賓館、飯店及招待所客房內及機關、學校、企業、住(zhu)宅(zhai)等(deng)建(jian)筑物(wu)內的(de)插座回路(lu);
(6)游泳池、噴水池、浴(yu)池的水中照明(ming)設備;
(7)安裝在水(shui)中(zhong)的(de)供電線(xian)路和設備;
(8)醫(yi)院在直接接觸人體的電氣醫(yi)用設備;
(9)其他需要安(an)裝漏(lou)(lou)電(dian)(dian)(dian)保(bao)護(hu)(hu)(hu)(hu)器的(de)(de)場所。 漏(lou)(lou)電(dian)(dian)(dian)保(bao)護(hu)(hu)(hu)(hu)器的(de)(de)安(an)裝、檢(jian)查等應(ying)由專業電(dian)(dian)(dian)工負責(ze)進行。對電(dian)(dian)(dian)工應(ying)進行有(you)關漏(lou)(lou)電(dian)(dian)(dian)保(bao)護(hu)(hu)(hu)(hu)器知識(shi)的(de)(de)培訓、考(kao)核。內(nei)容包括漏(lou)(lou)電(dian)(dian)(dian)保(bao)護(hu)(hu)(hu)(hu)器的(de)(de)原理、結構、性能、安(an)裝使用要求、檢(jian)查測試方法(fa)、安(an)全管(guan)理等。
四(si)、安(an)全電壓
把(ba)可能(neng)加在(zai)人身上的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)限制在(zai)某一范圍之內，使(shi)(shi)(shi)得(de)在(zai)這種電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)下(xia)，通過(guo)人體(ti)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流不超(chao)過(guo)允許的(de)(de)范圍。這種電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)就叫(jiao)做(zuo)安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，也叫(jiao)做(zuo)安全(quan)(quan)特(te)低電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。但(dan)應(ying)注(zhu)意，任何情況下(xia)都(dou)不能(neng)把(ba)安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)理解為絕對(dui)沒(mei)有危(wei)(wei)險(xian)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。具(ju)有安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)(de)設備屬于(yu)Ⅲ設備。 我國確定的(de)(de)安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)標(biao)準是42V、36V、24V、12V、 6V。特(te)別(bie)危(wei)(wei)險(xian)環(huan)境中(zhong)使(shi)(shi)(shi)用(yong)(yong)的(de)(de)手(shou)(shou)持電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)動工具(ju)應(ying)采用(yong)(yong)42V安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya);有電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)擊危(wei)(wei)險(xian)環(huan)境中(zhong)，使(shi)(shi)(shi)用(yong)(yong)的(de)(de)手(shou)(shou)持式照(zhao)明(ming)燈和(he)局部照(zhao)明(ming)燈應(ying)采用(yong)(yong)36V或24V安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya);金(jin)屬容(rong)器內、特(te)別(bie)潮濕(shi)處等特(te)別(bie)危(wei)(wei)險(xian)環(huan)境中(zhong)使(shi)(shi)(shi)用(yong)(yong)的(de)(de)手(shou)(shou)持式照(zhao)明(ming)燈應(ying)采用(yong)(yong)12V安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya);在(zai)水下(xia)作業等場所工作應(ying)使(shi)(shi)(shi)用(yong)(yong)6V安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。 當電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)氣設備采用(yong)(yong)超(chao)過(guo)24V的(de)(de)安全(quan)(quan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)時，必須采取防止直接接觸(chu)帶電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)體(ti)的(de)(de)保護措施。
五、安全間距
安(an)全間(jian)距(ju)是指(zhi)在帶電(dian)(dian)體(ti)與(yu)地面之間(jian)、帶電(dian)(dian)體(ti)與(yu)其他設施、設備(bei)(bei)之間(jian)、帶電(dian)(dian)體(ti)與(yu)帶電(dian)(dian)體(ti)之間(jian)保持的(de)一(yi)定安(an)全距(ju)離(li)，簡(jian)稱間(jian)距(ju)。設置安(an)全間(jian)距(ju)的(de)目的(de)是：防止人(ren)體(ti)觸及或(huo)接近(jin)帶電(dian)(dian)體(ti)造成(cheng)觸電(dian)(dian)事故;防止車輛或(huo)其他物體(ti)碰撞或(huo)過(guo)分接近(jin)帶電(dian)(dian)體(ti)造成(cheng)事故;防止電(dian)(dian)氣短路(lu)事故、過(guo)電(dian)(dian)壓(ya)放電(dian)(dian)和(he)火災(zai)事故;便于操作(zuo)。安(an)全間(jian)距(ju)的(de)大小取決于電(dian)(dian)壓(ya)高低、設備(bei)(bei)類型、安(an)裝方式等(deng)因素。
1.線(xian)(xian)路(lu)(lu)(lu)(lu)間(jian)距(ju)(ju)(ju)(ju)(ju)(ju) 架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)導(dao)(dao)(dao)線(xian)(xian)與地面或(huo)水(shui)(shui)面的(de)(de)(de)距(ju)(ju)(ju)(ju)(ju)(ju)離(li)不(bu)應(ying)(ying)低(di)于表(biao)(biao)(biao)2—1所列的(de)(de)(de)數值。 表(biao)(biao)(biao)2-1 導(dao)(dao)(dao)線(xian)(xian)與地面或(huo)水(shui)(shui)面的(de)(de)(de)最(zui)(zui)小距(ju)(ju)(ju)(ju)(ju)(ju)離(li) (單(dan)位(wei)：m) 線(xian)(xian)路(lu)(lu)(lu)(lu)經過地區 線(xian)(xian)路(lu)(lu)(lu)(lu)電壓(kV) 1以(yi)(yi)下(xia)(xia) 10 35 居民區 非居民區 交(jiao)通困難地區 不(bu)能通航或(huo)浮運的(de)(de)(de)河、湖冬季(ji)水(shui)(shui)面(或(huo)冰面) 不(bu)能通航或(huo)浮運的(de)(de)(de)河、湖最(zui)(zui)高(gao)水(shui)(shui)面(50年(nian)一遇的(de)(de)(de)洪水(shui)(shui)水(shui)(shui)面) 6 5 4 5 3 6.5 5.5 4.5 5 3 7 6 5 5.5 3 架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)應(ying)(ying)避免跨(kua)越建(jian)筑(zhu)(zhu)(zhu)物(wu)。架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)不(bu)應(ying)(ying)跨(kua)越可燃(ran)材料作(zuo)屋頂(ding)的(de)(de)(de)建(jian)筑(zhu)(zhu)(zhu)物(wu)。架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)必須跨(kua)越建(jian)筑(zhu)(zhu)(zhu)物(wu)時，應(ying)(ying)與有(you)關(guan)部門協商并取得有(you)關(guan)部門的(de)(de)(de)同意。架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)與建(jian)筑(zhu)(zhu)(zhu)物(wu)的(de)(de)(de)距(ju)(ju)(ju)(ju)(ju)(ju)離(li)不(bu)應(ying)(ying)小于下(xia)(xia)表(biao)(biao)(biao)2—2的(de)(de)(de)數值。 表(biao)(biao)(biao)2-2 導(dao)(dao)(dao)線(xian)(xian)與建(jian)筑(zhu)(zhu)(zhu)物(wu)的(de)(de)(de)最(zui)(zui)小距(ju)(ju)(ju)(ju)(ju)(ju)離(li)(單(dan)位(wei)：m) 線(xian)(xian)路(lu)(lu)(lu)(lu)電壓(kV) 1以(yi)(yi)下(xia)(xia) 10 35 水(shui)(shui)平距(ju)(ju)(ju)(ju)(ju)(ju)離(li) 1.0 1.5 3.0 垂(chui)直(zhi)距(ju)(ju)(ju)(ju)(ju)(ju)離(li) 2.5 3.0 4.0 架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)導(dao)(dao)(dao)線(xian)(xian)與街道或(huo)廠區樹木(mu)的(de)(de)(de)距(ju)(ju)(ju)(ju)(ju)(ju)離(li)不(bu)應(ying)(ying)低(di)于表(biao)(biao)(biao)2—3所列的(de)(de)(de)數值。 表(biao)(biao)(biao)2-3 導(dao)(dao)(dao)線(xian)(xian)與樹木(mu)的(de)(de)(de)最(zui)(zui)小距(ju)(ju)(ju)(ju)(ju)(ju)離(li) (單(dan)位(wei)：m) 線(xian)(xian)路(lu)(lu)(lu)(lu)電壓(kV) 1以(yi)(yi)下(xia)(xia) 10 35 水(shui)(shui)平距(ju)(ju)(ju)(ju)(ju)(ju)離(li) 1.0 2.0 — 垂(chui)直(zhi)距(ju)(ju)(ju)(ju)(ju)(ju)離(li) 1.0 1.5 3.0 架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)也(ye)應(ying)(ying)與有(you)爆(bao)炸危險的(de)(de)(de)廠房或(huo)有(you)火災危險的(de)(de)(de)廠房保持(chi)必要的(de)(de)(de)防(fang)火間(jian)距(ju)(ju)(ju)(ju)(ju)(ju)。架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)與鐵道、道路(lu)(lu)(lu)(lu)、索道及其他架空(kong)(kong)線(xian)(xian)路(lu)(lu)(lu)(lu)之間(jian)的(de)(de)(de)距(ju)(ju)(ju)(ju)(ju)(ju)離(li)應(ying)(ying)符(fu)合(he)有(you)關(guan)規定。
2.設(she)備間距(ju) 配電(dian)裝置(zhi)(zhi)(zhi)的布(bu)置(zhi)(zhi)(zhi)應考慮到(dao)設(she)備搬運、檢修(xiu)、操作和(he)試(shi)驗的方便性。為(wei)了工作人員安全(quan)，配電(dian)裝置(zhi)(zhi)(zhi)以外需要保持必要的安全(quan)通道。如在(zai)配電(dian)室內，低壓配電(dian)裝置(zhi)(zhi)(zhi)正面通道寬度，單列布(bu)置(zhi)(zhi)(zhi)時(shi)應不小于1.5m。室內變壓器與(yu)四壁應留(liu)有適當距(ju)離(li)。
3.檢修間(jian)距(ju) 檢修間(jian)距(ju)是指在維護檢修中人體(ti)(ti)及(ji)所帶工具與(yu)帶電體(ti)(ti)之間(jian)必須(xu)保(bao)持的足夠的安(an)(an)全距(ju)離(li)(li)(li)。在低壓工作中，人體(ti)(ti)及(ji)所攜帶的工具與(yu)帶電體(ti)(ti)距(ju)離(li)(li)(li)不應小于(yu) 0.1m。 起重機械在架(jia)空線(xian)路附近進(jin)行作業時(shi)，要注(zhu)意其與(yu)線(xian)路導線(xian)之間(jian)應保(bao)持足夠的安(an)(an)全距(ju)離(li)(li)(li)。可參考表2—4。 表2—4 起重機械與(yu)線(xian)路導線(xian)的最小距(ju)離(li)(li)(li) (單位：m) 電壓(kV) 1以下 10 35 距(ju)離(li)(li)(li) 1.5 2 4
六、接(jie)零與(yu)接(jie)地(di)
在工廠里，使(shi)用的(de)(de)(de)(de)(de)電(dian)(dian)氣(qi)設(she)備很(hen)多。為(wei)了防止觸(chu)電(dian)(dian)，通常可采(cai)用絕緣、隔離(li)等技(ji)術(shu)措施(shi)以保(bao)障用電(dian)(dian)安(an)全。但(dan)工人在生(sheng)產過程中經常接(jie)觸(chu)的(de)(de)(de)(de)(de)是電(dian)(dian)氣(qi)設(she)備不(bu)帶電(dian)(dian)的(de)(de)(de)(de)(de)外(wai)殼(ke)或與(yu)其連接(jie)的(de)(de)(de)(de)(de)金屬(shu)體(ti)。這(zhe)樣當設(she)備萬一發生(sheng)漏電(dian)(dian)故(gu)障時(shi)，平時(shi)不(bu)帶電(dian)(dian)的(de)(de)(de)(de)(de)外(wai)殼(ke)就帶電(dian)(dian)，并與(yu)大地之間(jian)存(cun)在電(dian)(dian)壓(ya)，就會(hui)使(shi)操作人員觸(chu)電(dian)(dian)。這(zhe)種意外(wai)的(de)(de)(de)(de)(de)觸(chu)電(dian)(dian)是非常危險的(de)(de)(de)(de)(de)。為(wei)了解決這(zhe)個不(bu)安(an)全的(de)(de)(de)(de)(de)問(wen)題，采(cai)取的(de)(de)(de)(de)(de)主要的(de)(de)(de)(de)(de)安(an)全措施(shi)，就是對電(dian)(dian)氣(qi)設(she)備的(de)(de)(de)(de)(de)外(wai)殼(ke)進行保(bao)護接(jie)地或保(bao)護接(jie)零。
1.保護接(jie)(jie)零(ling)(ling)(ling) 將電(dian)(dian)氣設(she)備在正常情況下不帶電(dian)(dian)的(de)(de)(de)金(jin)屬(shu)外(wai)殼(ke)與(yu)變壓器中性(xing)點引(yin)出的(de)(de)(de)工作零(ling)(ling)(ling)線(xian)或(huo)保護零(ling)(ling)(ling)線(xian)相(xiang)連接(jie)(jie)，這種(zhong)方式(shi)(shi)稱為保護接(jie)(jie)零(ling)(ling)(ling)。當某相(xiang)帶電(dian)(dian)部分碰觸電(dian)(dian)氣設(she)備的(de)(de)(de)金(jin)屬(shu)外(wai)殼(ke)時，通過設(she)備外(wai)殼(ke)形成(cheng)該相(xiang)線(xian)對零(ling)(ling)(ling)線(xian)的(de)(de)(de)單相(xiang)短(duan)路回路，該短(duan)路電(dian)(dian)流較大(da)，足以保證在最短(duan)的(de)(de)(de)時間內使(shi)熔(rong)絲熔(rong)斷、保護裝置或(huo)自動(dong)開關跳閘，從而(er)切斷電(dian)(dian)流，保障了人身(shen)安(an)全。保護接(jie)(jie)零(ling)(ling)(ling)的(de)(de)(de)應(ying)用范圍，主(zhu)要是(shi)用于三(san)相(xiang)四線(xian)制中性(xing)點直(zhi)接(jie)(jie)接(jie)(jie)地供電(dian)(dian)系統中的(de)(de)(de)電(dian)(dian)氣設(she)備。在工廠里也就是(shi)用于380/220伏的(de)(de)(de)低(di)壓設(she)備上(shang)。圖2 —1是(shi)保護接(jie)(jie)零(ling)(ling)(ling)示意圖。 在中性(xing)點直(zhi)接(jie)(jie)接(jie)(jie)地的(de)(de)(de)低(di)壓配電(dian)(dian)系統中，為確保保護接(jie)(jie)零(ling)(ling)(ling)方式(shi)(shi)的(de)(de)(de)安(an)全可靠，防止零(ling)(ling)(ling)線(xian)斷線(xian)所造(zao)成(cheng)的(de)(de)(de)危害，系統中除了工作接(jie)(jie)地外(wai)，還必須(xu)在整個零(ling)(ling)(ling)線(xian)的(de)(de)(de)其他(ta)部位再進行(xing)必要的(de)(de)(de)接(jie)(jie)地。這種(zhong)接(jie)(jie)地稱為重復接(jie)(jie)地。
2.保護(hu)(hu)接(jie)(jie)(jie)地(di) 保護(hu)(hu)接(jie)(jie)(jie)地(di)是(shi)指(zhi)將電(dian)氣(qi)設(she)備平時不帶(dai)電(dian)的(de)(de)金(jin)屬(shu)外殼用專門(men)設(she)置的(de)(de)接(jie)(jie)(jie)地(di)裝置實行良好(hao)的(de)(de)金(jin)屬(shu)性連接(jie)(jie)(jie)。其情況如圖2-2所示。保護(hu)(hu)接(jie)(jie)(jie)地(di)的(de)(de)作用是(shi)當設(she)備金(jin)屬(shu)外殼意(yi)外帶(dai)電(dian)時，將其對地(di)電(dian)壓限制在規定的(de)(de)安全范圍(wei)內，消除或減小觸電(dian)的(de)(de)危(wei)險。保護(hu)(hu)接(jie)(jie)(jie)地(di)最常用于低壓不接(jie)(jie)(jie)地(di)配電(dian)網中(zhong)的(de)(de)電(dian)氣(qi)設(she)備。