防電(dian)(dian)措(cuo)施(shi)，接地(di)措(cuo)施(shi)都是(shi)按照左鄰右火這(zhe)種模(mo)式來設計的(de)(de)(de)，也就(jiu)(jiu)是(shi)說(shuo)，有(you)(you)些，用電(dian)(dian)器的(de)(de)(de)開(kai)關(guan)都是(shi)設計，控(kong)制(zhi)火線(xian)的(de)(de)(de)，如果接反了(le)，也就(jiu)(jiu)是(shi)說(shuo)，沒(mei)有(you)(you)控(kong)制(zhi)盜(dao)火線(xian)，那么就(jiu)(jiu)沒(mei)有(you)(you)起到電(dian)(dian)路，徹底斷(duan)開(kai)的(de)(de)(de)作用是(shi)由物(wu)(wu)質內部的(de)(de)(de)原子(zi)(zi)核(he)中(zhong)的(de)(de)(de)帶電(dian)(dian)粒子(zi)(zi)有(you)(you)規(gui)則的(de)(de)(de)運(yun)動所(suo)(suo)形成的(de)(de)(de)（這(zhe)個初級(ji)中(zhong)學物(wu)(wu)理(li)課上(shang)有(you)(you)。）這(zhe)里所(suo)(suo)要說(shuo)的(de)(de)(de)是(shi)人(ren)們是(shi)怎(zen)么樣讓電(dian)(dian)子(zi)(zi)有(you)(you)規(gui)則的(de)(de)(de)在導線(xian)中(zhong)運(yun)動的(de)(de)(de)呢(ni)？這(zhe)就(jiu)(jiu)要說(shuo)的(de)(de)(de)發電(dian)(dian)機了(le)。

無論(lun)怎么(me)接(jie)(jie)反電(dian)(dian)(dian)壓(ya)都(dou)不變，而且大(da)部分家用電(dian)(dian)(dian)器(qi)（除部分電(dian)(dian)(dian)機、純電(dian)(dian)(dian)阻電(dian)(dian)(dian)器(qi)）都(dou)是(shi)(shi)在電(dian)(dian)(dian)器(qi)內部交流變直流后(hou)供電(dian)(dian)(dian)，所以接(jie)(jie)反不影響正常用電(dian)(dian)(dian)。但是(shi)(shi)接(jie)(jie)反零(ling)火線(xian)給生活帶(dai)來許多隱患。晚(wan)上(shang)關了燈(deng)以后(hou)有可能燈(deng)仍然微亮(liang)。因(yin)為(wei)燈(deng)控電(dian)(dian)(dian)路的接(jie)(jie)線(xian)，零(ling)線(xian)進燈(deng)火線(xian)進開(kai)關，開(kai)關都(dou)是(shi)(shi)接(jie)(jie)在火線(xian)上(shang)，如果開(kai)關控制的零(ling)線(xian)，即使關了燈(deng)，燈(deng)頭(tou)(tou)仍然連著(zhu)火線(xian)，這時候觸碰燈(deng)頭(tou)(tou)非常危險。

插(cha)座內接(jie)(jie)頭不分零(ling)線火線，但地線卻不能接(jie)(jie)錯。交流單相電(dian)是不分正負極，故零(ling)火線接(jie)(jie)反(fan)沒有安(an)全隱(yin)患。一定會(hui)有洪(hong)水(shui)的狀況。所以(yi)零(ling)火接(jie)(jie)反(fan)會(hui)造成短(duan)路(lu)，就像火藥遇見了明火，會(hui)發生火花(hua)現象，瞬間(jian)導(dao)(dao)致溫度上(shang)升幾(ji)百(bai)攝氏(shi)度，會(hui)引起火災，而且(qie)會(hui)導(dao)(dao)致家用電(dian)器部分電(dian)路(lu)板損壞，因為瞬間(jian)電(dian)壓不穩導(dao)(dao)致。

家用(yong)(yong)(yong)(yong)220伏(fu)電(dian)(dian)，零線(xian)(xian)火線(xian)(xian)正反接(jie)(jie)沒(mei)事的(de)，不過嚴謹(jin)起見，請按照(zhao)開關(guan)指示的(de)接(jie)(jie)線(xian)(xian)。不規范的(de)接(jie)(jie)線(xian)(xian)雖(sui)然能用(yong)(yong)(yong)(yong)，但(dan)后期會留下隱患。家用(yong)(yong)(yong)(yong)開關(guan)是連接(jie)(jie)在火線(xian)(xian)上的(de)，如果開關(guan)是在零線(xian)(xian)上，電(dian)(dian)器(qi)可能還會帶電(dian)(dian)的(de)。現實生(sheng)活中(zhong)，有(you)許多(duo)人在用(yong)(yong)(yong)(yong)完電(dian)(dian)器(qi)之后，都沒(mei)有(you)拔掉(diao)用(yong)(yong)(yong)(yong)電(dian)(dian)器(qi)插(cha)頭的(de)習慣，如果不按“左零右火”規則(ze)安裝(zhuang)插(cha)座，這樣一(yi)來關(guan)掉(diao)的(de)就有(you)可能是“零線(xian)(xian)”，此(ci)時(shi)的(de)用(yong)(yong)(yong)(yong)電(dian)(dian)器(qi)是仍然處于(yu)帶電(dian)(dian)狀態當(dang)中(zhong)的(de)。