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(ji)燈(deng)當(dang)有(you)市電(dian)(dian)(dian)時．通過變壓(ya)器B降壓(ya)、整(zheng)流、濾(lv)波．此時6V的直(zhi)流繼(ji)電(dian)(dian)(dian)吸合，常開觸(chu)點(dian)閉合，使整(zheng)流后(hou)的直(zhi)流電(dian)(dian)(dian)通過R1降壓(ya)向電(dian)(dian)(dian)瓶充電(dian)(dian)(dian)，LED作(zuo)電(dian)(dian)(dian)源指示(shi)燈(deng)。當(dang)市電(dian)(dian)(dian)停電(dian)(dian)(dian)時，6V的繼(ji)電(dian)(dian)(dian)器失電(dian)(dian)(dian)．常開點(dian)斷開，接通常閉點(dian)，應急(ji)燈(deng)泡ZD接到電(dian)(dian)(dian)瓶端(duan)．得電(dian)(dian)(dian)發光(guang)起到應急(ji)照明作(zuo)用。市電(dian)(dian)(dian)恢復時．回復到上述(shu)過程。

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(ran)而(er)故障也出現得多。

消防應急燈常見故障及維修

由(you)于電(dian)瓶(ping)長期充(chong)電(dian)。又無充(chong)滿保護電(dian)路．故最容(rong)易壞，其次(ci)是變壓器，再就(jiu)是驅(qu)動三極(ji)管(guan)Q2(或Q3)，如果燈泡長期被點(dian)亮。管(guan)于發熱，也(ye)容(rong)易損(sun)壞。一般更換這幾個(ge)元件(jian)便能正常工作。

當市電(dian)正常(chang)供電(dian)時。通過(guo)變(bian)壓(ya)(ya)(ya)(ya)(ya)器降壓(ya)(ya)(ya)(ya)(ya)、整流(liu)、濾波，在C1上得到大約13V的直流(liu)電(dian)壓(ya)(ya)(ya)(ya)(ya)。該電(dian)壓(ya)(ya)(ya)(ya)(ya)經R3、Q1、D6給電(dian)瓶(ping)充(chong)電(dian)。Q1的基極(ji)(ji)接有穩(wen)壓(ya)(ya)(ya)(ya)(ya)二極(ji)(ji)管(guan)DZ1，電(dian)阻R4既是(shi)Q1基極(ji)(ji)的偏流(liu)電(dian)阻，又(you)是(shi)穩(wen)壓(ya)(ya)(ya)(ya)(ya)管(guan)的限流(liu)電(dian)阻，使Q1基極(ji)(ji)約為(wei)8.9V，這(zhe)樣充(chong)電(dian)電(dian)壓(ya)(ya)(ya)(ya)(ya)受到限制，最高為(wei)7.6V．可保護電(dian)池。其充(chong)電(dian)電(dian)流(liu)隨(sui)著電(dian)瓶(ping)的電(dian)壓(ya)(ya)(ya)(ya)(ya)而(er)變(bian)化，電(dian)壓(ya)(ya)(ya)(ya)(ya)越(yue)低充(chong)電(dian)電(dian)流(liu)越(yue)大，反之越(yue)小(xiao)。在充(chong)電(dian)狀態，Q2飽(bao)和導通，Q3由(you)于D7、R10的作用而(er)截止(zhi)，Q4也(ye)截止(zhi)，所以照明燈ZD1、ZD2不亮。

當220v交流(liu)(liu)電(dian)(dian)因(yin)故停電(dian)(dian)時，變壓(ya)器B1次級無輸出電(dian)(dian)．電(dian)(dian)路(lu)中直流(liu)(liu)13V電(dian)(dian)壓(ya)消失，D7正極(ji)無電(dian)(dian)壓(ya)，由于Q2在(zai)停電(dian)(dian)前(qian)處于飽和導通(tong)狀態(tai)(tai)，所以Q3立即(ji)導通(tong)，Q4基極(ji)電(dian)(dian)位升(sheng)高，Q4也隨之導通(tong)，照(zhao)明(ming)燈(deng)DZ1、DZ2被(bei)點(dian)(dian)亮(liang)。Q4導通(tong)后其集電(dian)(dian)極(ji)為低(di)電(dian)(dian)位，由于R1跨接在(zai)Q4集電(dian)(dian)極(ji)與Q3基極(ji)之間，Q3基極(ji)電(dian)(dian)位下降，維(wei)持Q3的導通(tong)狀態(tai)(tai)，照(zhao)明(ming)燈(deng)一直被(bei)點(dian)(dian)亮(liang)。紅色LED作為充電(dian)(dian)指示(shi)燈(deng)，綠色LED作為主電(dian)(dian)源(yuan)指示(shi)燈(deng)。紅燈(deng)亮(liang)表(biao)示(shi)電(dian)(dian)瓶正在(zai)充電(dian)(dian)，綠燈(deng)亮(liang)表(biao)示(shi)有交流(liu)(liu)220V電(dian)(dian)壓(ya)。0N／OFF為照(zhao)明(ming)燈(deng)的開關按(an)鈕，220V交流(liu)(liu)電(dian)(dian)源(yuan)停電(dian)(dian)時．可以通(tong)過此(ci)按(an)鈕打(da)開或關閉照(zhao)明(ming)燈(deng)。

當應急燈出故障(zhang)時．可(ke)先觀察(cha)兩(liang)指(zhi)(zhi)示燈的(de)(de)(de)工作狀態。交流220V供電(dian)(dian)(dian)(dian)(dian)(dian)正(zheng)常(chang)時．綠(lv)色指(zhi)(zhi)示燈應亮(liang)(liang)，電(dian)(dian)(dian)(dian)(dian)(dian)瓶充電(dian)(dian)(dian)(dian)(dian)(dian)紅色指(zhi)(zhi)示燈也(ye)應亮(liang)(liang)。如果綠(lv)燈不亮(liang)(liang)，則(ze)(ze)應檢(jian)查變(bian)壓(ya)(ya)器次級是(shi)否(fou)有9V交流電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，電(dian)(dian)(dian)(dian)(dian)(dian)容C1兩(liang)端應有13V左(zuo)右(you)的(de)(de)(de)直流電(dian)(dian)(dian)(dian)(dian)(dian)。如果兩(liang)處都沒(mei)有電(dian)(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)(dian)源(綠(lv)色)指(zhi)(zhi)示燈亮(liang)(liang)，充電(dian)(dian)(dian)(dian)(dian)(dian)(紅色)指(zhi)(zhi)示燈不亮(liang)(liang)，可(ke)測Q1發射極有無7V左(zuo)右(you)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，如無電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，則(ze)(ze)應檢(jian)查Q1之前(qian)的(de)(de)(de)相應元件。檢(jian)修(xiu)中，可(ke)斷(duan)開電(dian)(dian)(dian)(dian)(dian)(dian)瓶正(zheng)極，測量應急燈的(de)(de)(de)開路充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)與通路充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，正(zheng)常(chang)時應為(wei)7V左(zuo)右(you)，充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流約為(wei)450mA。如果電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)過高，則(ze)(ze)應查Q1是(shi)否(fou)擊穿短(duan)路，DZ1、R14是(shi)否(fou)開路，過高的(de)(de)(de)充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，將造成電(dian)(dian)(dian)(dian)(dian)(dian)瓶過充損壞。

交流(liu)220V停電(dian)時．照明燈ZD1、ZD2不亮．首(shou)先查燈泡是否損壞．再檢查三極管Q2、Q3、Q4及相關(guan)元件是否損壞；電(dian)瓶老(lao)化(hua)等。