消防應急燈廣泛用于公共場所的走廊、消防通道內。現在各廠礦企業、大型超市、醫院學校等都安裝了這種應急燈。市場上眾多的消防應急燈具是由消防公安及安監部門監制的產品．品種繁多，但功能基本一致。當市電停電時，消防應急燈自動點亮，來電時自動熄滅。消防應急燈作為一種備用照明設備，在燈具內裝有停電時提供電源的蓄電池G(或稱電瓶)。由于應急燈長時間與市電并聯在一起工作，所以容易出現故障。

消防應急燈電路原理

應急燈當有市(shi)電(dian)(dian)時．通(tong)過(guo)變(bian)壓器B降壓、整流、濾波．此時6V的(de)直(zhi)(zhi)流繼電(dian)(dian)吸合(he)，常開(kai)觸點閉合(he)，使整流后的(de)直(zhi)(zhi)流電(dian)(dian)通(tong)過(guo)R1降壓向(xiang)電(dian)(dian)瓶(ping)充電(dian)(dian)，LED作電(dian)(dian)源指(zhi)示燈。當市(shi)電(dian)(dian)停(ting)電(dian)(dian)時，6V的(de)繼電(dian)(dian)器失電(dian)(dian)．常開(kai)點斷(duan)開(kai)，接(jie)通(tong)常閉點，應急燈泡ZD接(jie)到電(dian)(dian)瓶(ping)端．得(de)電(dian)(dian)發光起(qi)到應急照(zhao)明(ming)作用。市(shi)電(dian)(dian)恢復時．回(hui)復到上述過(guo)程。

該圖片由注冊用戶"洋洋盈耳"提供，版權聲明反饋

消防應急燈常見故障原因

(1)電瓶長期充電，電液干枯，過早損壞。(2)變壓器長期通電過熱燒壞。(3)最常見的是繼電器線圈長期通電燒壞或其接點燒蝕。這種燈較簡易價格低．然而故障(zhang)也(ye)出現得多。

消防應急燈常見故障及維修

由(you)于(yu)電(dian)瓶長期充電(dian)。又無充滿保護電(dian)路．故最容易(yi)壞，其次是變(bian)壓器，再(zai)就(jiu)是驅(qu)動三極(ji)管Q2(或Q3)，如(ru)果燈泡長期被(bei)點(dian)亮(liang)。管于(yu)發熱，也(ye)容易(yi)損壞。一般更換這幾個元件便(bian)能(neng)正常(chang)工作。

當市電(dian)正常供電(dian)時。通過(guo)變壓(ya)(ya)(ya)器降壓(ya)(ya)(ya)、整(zheng)流、濾波，在C1上得到大約13V的直流電(dian)壓(ya)(ya)(ya)。該電(dian)壓(ya)(ya)(ya)經(jing)R3、Q1、D6給電(dian)瓶充(chong)(chong)電(dian)。Q1的基極接有穩(wen)壓(ya)(ya)(ya)二極管DZ1，電(dian)阻(zu)R4既(ji)是Q1基極的偏流電(dian)阻(zu)，又是穩(wen)壓(ya)(ya)(ya)管的限(xian)流電(dian)阻(zu)，使Q1基極約為(wei)8.9V，這樣充(chong)(chong)電(dian)電(dian)壓(ya)(ya)(ya)受到限(xian)制，最高為(wei)7.6V．可保護電(dian)池(chi)。其充(chong)(chong)電(dian)電(dian)流隨著電(dian)瓶的電(dian)壓(ya)(ya)(ya)而(er)變化(hua)，電(dian)壓(ya)(ya)(ya)越(yue)低充(chong)(chong)電(dian)電(dian)流越(yue)大，反之越(yue)小(xiao)。在充(chong)(chong)電(dian)狀態，Q2飽(bao)和導通，Q3由于D7、R10的作用而(er)截止，Q4也截止，所以照明燈ZD1、ZD2不亮。

當220v交(jiao)流電(dian)(dian)(dian)因故停電(dian)(dian)(dian)時，變壓(ya)器B1次(ci)級無(wu)輸出電(dian)(dian)(dian)．電(dian)(dian)(dian)路(lu)中直流13V電(dian)(dian)(dian)壓(ya)消失，D7正極無(wu)電(dian)(dian)(dian)壓(ya)，由于Q2在停電(dian)(dian)(dian)前處于飽和(he)導(dao)(dao)通狀(zhuang)態，所以Q3立即導(dao)(dao)通，Q4基(ji)極電(dian)(dian)(dian)位(wei)升高，Q4也隨(sui)之導(dao)(dao)通，照明(ming)燈(deng)DZ1、DZ2被點亮(liang)。Q4導(dao)(dao)通后其集(ji)電(dian)(dian)(dian)極為(wei)(wei)低電(dian)(dian)(dian)位(wei)，由于R1跨接(jie)在Q4集(ji)電(dian)(dian)(dian)極與Q3基(ji)極之間，Q3基(ji)極電(dian)(dian)(dian)位(wei)下降(jiang)，維持Q3的(de)導(dao)(dao)通狀(zhuang)態，照明(ming)燈(deng)一(yi)直被點亮(liang)。紅色LED作為(wei)(wei)充(chong)電(dian)(dian)(dian)指(zhi)示(shi)(shi)(shi)燈(deng)，綠色LED作為(wei)(wei)主電(dian)(dian)(dian)源指(zhi)示(shi)(shi)(shi)燈(deng)。紅燈(deng)亮(liang)表示(shi)(shi)(shi)電(dian)(dian)(dian)瓶(ping)正在充(chong)電(dian)(dian)(dian)，綠燈(deng)亮(liang)表示(shi)(shi)(shi)有交(jiao)流220V電(dian)(dian)(dian)壓(ya)。0N／OFF為(wei)(wei)照明(ming)燈(deng)的(de)開關按(an)鈕，220V交(jiao)流電(dian)(dian)(dian)源停電(dian)(dian)(dian)時．可以通過此按(an)鈕打開或關閉(bi)照明(ming)燈(deng)。

當應急燈出故障時(shi)．可先(xian)觀察兩指示(shi)燈的工作狀態。交流(liu)220V供電(dian)(dian)(dian)(dian)(dian)正(zheng)常時(shi)．綠(lv)色指示(shi)燈應(ying)(ying)(ying)亮(liang)，電(dian)(dian)(dian)(dian)(dian)瓶(ping)充(chong)電(dian)(dian)(dian)(dian)(dian)紅(hong)色指示(shi)燈也(ye)應(ying)(ying)(ying)亮(liang)。如(ru)果綠(lv)燈不(bu)(bu)亮(liang)，則應(ying)(ying)(ying)檢查(cha)變(bian)壓(ya)(ya)器次級是(shi)否(fou)有(you)(you)9V交流(liu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，電(dian)(dian)(dian)(dian)(dian)容C1兩端應(ying)(ying)(ying)有(you)(you)13V左(zuo)右(you)(you)的直流(liu)電(dian)(dian)(dian)(dian)(dian)。如(ru)果兩處都沒有(you)(you)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。一般是(shi)變(bian)壓(ya)(ya)器B1損壞。電(dian)(dian)(dian)(dian)(dian)源(yuan)(綠(lv)色)指示(shi)燈亮(liang)，充(chong)電(dian)(dian)(dian)(dian)(dian)(紅(hong)色)指示(shi)燈不(bu)(bu)亮(liang)，可測Q1發射極有(you)(you)無(wu)7V左(zuo)右(you)(you)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，如(ru)無(wu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，則應(ying)(ying)(ying)檢查(cha)Q1之前的相應(ying)(ying)(ying)元件。檢修(xiu)中，可斷(duan)開電(dian)(dian)(dian)(dian)(dian)瓶(ping)正(zheng)極，測量應(ying)(ying)(ying)急(ji)燈的開路(lu)(lu)充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)與通路(lu)(lu)充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，正(zheng)常時(shi)應(ying)(ying)(ying)為7V左(zuo)右(you)(you)，充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)約為450mA。如(ru)果電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)過高，則應(ying)(ying)(ying)查(cha)Q1是(shi)否(fou)擊穿短(duan)路(lu)(lu)，DZ1、R14是(shi)否(fou)開路(lu)(lu)，過高的充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，將造成電(dian)(dian)(dian)(dian)(dian)瓶(ping)過充(chong)損壞。

交流220V停(ting)電時．照明燈(deng)ZD1、ZD2不亮．首先查(cha)燈(deng)泡是否(fou)損壞．再檢查(cha)三極管(guan)Q2、Q3、Q4及相關元件是否(fou)損壞；電瓶老化等。