還(huan)記(ji)的前幾年那位因為(wei)在手機(ji)充電時(shi)打(da)電話(hua)而被電擊而亡的美麗空姐嗎(ma)？誰也沒(mei)有想到這(zhe)樣一個(ge)非常(chang)正常(chang)的行為(wei)居(ju)然會造成威脅生命，那么導致這(zhe)位空姐觸電而亡的原因究竟是(shi)什么呢？今(jin)天的電源工程師(shi)就(jiu)為大家來解開這個謎題。

導致人觸電(dian)(dian)而亡的(de)不是因(yin)為充(chong)電(dian)(dian)時打電(dian)(dian)話，而是因(yin)為用了山(shan)寨(zhai)的(de)劣質(zhi)充(chong)電(dian)(dian)器(qi)。為什(shen)么山(shan)寨(zhai)充(chong)電(dian)(dian)器(qi)會這(zhe)么危險呢? 一個小(xiao)功率(lv)的(de)開關電(dian)(dian)源，它(ta)可將220v的(de)交(jiao)流(liu)電(dian)(dian)轉換為5v的(de)直流(liu)電(dian)(dian)，以供(gong)手(shou)機(ji)使用。

正品充電(dian)(dian)器(qi)大多使(shi)用一個小(xiao)集(ji)成電(dian)(dian)路(lu)提(ti)供(gong)振蕩信號，由開關晶體(ti)管(guan)放大后(hou)接入(ru)高頻變壓器(qi)的原(yuan)線圈(quan)(quan)，也有一些(xie)充電(dian)(dian)器(qi)使(shi)用雙晶體(ti)管(guan)自(zi)激(ji)的方(fang)式，而(er)山寨(zhai)充電(dian)(dian)器(qi)多使(shi)用單管(guan)自(zi)激(ji)的驅動方(fang)案，電(dian)(dian)源效率低(di)下，而(er)且缺少保護電(dian)(dian)路(lu)，安全性能低(di)，在(zai)過載或短(duan)路(lu)時(shi)不能自(zi)動切斷電(dian)(dian)源，而(er)使(shi)變壓器(qi)內部溫度升高，燒毀匝間絕緣(yuan)，從而(er)使(shi)原(yuan)、副線圈(quan)(quan)相連導致漏電(dian)(dian)。成為觸電(dian)(dian)事故的一個原(yuan)因。

線(xian)(xian)路板布線(xian)(xian)也是一個重要的(de)(de)原因，正規充(chong)(chong)電(dian)(dian)器PCB布線(xian)(xian)時線(xian)(xian)路之(zhi)間有足夠的(de)(de)安全(quan)距(ju)離(li)，如初級(ji)電(dian)(dian)路和次(ci)級(ji)電(dian)(dian)路之(zhi)間的(de)(de)電(dian)(dian)氣間隙(xi)不(bu)能(neng)低(di)于4.0mm，爬電(dian)(dian)距(ju)離(li)不(bu)能(neng)低(di)于6.4mm,距(ju)離(li)不(bu)足著應該開空槽保(bao)持絕(jue)緣。而山寨充(chong)(chong)電(dian)(dian)器初、次(ci)級(ji)只有1-3mm，甚至有些充(chong)(chong)電(dian)(dian)器初、次(ci)級(ji)之(zhi)間難以看到邊界(jie)，這也是導致是充(chong)(chong)電(dian)(dian)器觸電(dian)(dian)的(de)(de)重要原因。

另外(wai)(wai)正(zheng)規充電(dian)(dian)器使(shi)用(yong)(yong)耐壓3kv的(de)專用(yong)(yong)安規電(dian)(dian)容，而山寨(zhai)充電(dian)(dian)器使(shi)用(yong)(yong)普通瓷片電(dian)(dian)容，在(zai)交流電(dian)(dian)壓突增時易擊(ji)穿而發(fa)生危險。空姐的(de)觸電(dian)(dian)事(shi)故，有(you)一個重要條件就(jiu)是金屬手(shou)機(ji)外(wai)(wai)殼(ke)。金屬外(wai)(wai)殼(ke)的(de)手(shou)機(ji)通常與手(shou)機(ji)主板地(di)端(duan)相連，在(zai)手(shou)機(ji)充電(dian)(dian)時手(shou)機(ji)主板地(di)端(duan)又通過數據線連接充電(dian)(dian)器的(de)次(ci)(ci)級(ji)電(dian)(dian)路(lu)(lu)，如(ru)果充電(dian)(dian)器初、次(ci)(ci)級(ji)漏電(dian)(dian)（或(huo)短路(lu)(lu)），手(shou)機(ji)金屬外(wai)(wai)殼(ke)就(jiu)會(hui)帶220v高(gao)壓交流電(dian)(dian)，如(ru)果此時有(you)人使(shi)用(yong)(yong)手(shou)機(ji)，使(shi)用(yong)(yong)者(zhe)極(ji)易觸電(dian)(dian)。

所以充電器工(gong)廠(chang)可(ke)以告訴(su)大家，充電時打電話除了(le)會(hui)使(shi)手機更熱一些(xie)，本身是不(bu)會(hui)對人產生危險的。導致(zhi)人觸(chu)電而亡的是，劣質充電器的漏電行為。所以，請珍愛生命，遠離(li)沒有通(tong)過安規認(ren)證(zheng)的山寨(zhai)充電器。