應急燈的工作原理詳解

應(ying)急燈(deng)的工作原(yuan)理分為在供電正常時情況(kuang)下，停電情況(kuang)下，制作情況(kuang)下。

應急燈又稱方(fang)便(bian)燈,它(ta)不但可以在停電(dian)(dian)時(shi)作(zuo)照(zhao)明用,也(ye)可以在無(wu)文(wen)流供電(dian)(dian)電(dian)(dian)潭的情況下實現照(zhao)明等作(zuo)用。

在供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)正常(chang)時，J2得電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)吸(xi)合，其動(dong)觸點(dian)(dian)與“N/O（常(chang)開點(dian)(dian)）”接通(tong)，后備蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池正端與IC1的(de)反相端相聯。IC1（LM308）和D5、D6組成電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)比(bi)較 器，參考(kao)(kao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)由(you)D5、D6決定。這里用一(yi)個(ge)硅二極(ji)管（D5）和一(yi)個(ge)6.2V的(de)穩(wen)壓(ya)(ya)(ya)二極(ji)管（D6）組成6.9V的(de)參考(kao)(kao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，對充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)進(jin)行(xing)監控。當(dang)IC1 的(de)2腳輸入電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)（既蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)）低(di)于(yu)6.9V時，IC1的(de)6腳輸出高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)平(ping)，T1導(dao)通(tong)，J1得電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，其動(dong)觸點(dian)(dian)與“N/O（常(chang)開點(dian)(dian)）”接通(tong)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)通(tong)過R2對 蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，同時LED2點(dian)(dian)亮為充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)指示。改變R2阻值可(ke)調整充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)。隨著(zhu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)時間(jian)增(zeng)加，IC1的(de)2腳電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)逐(zhu)漸增(zeng)加，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)大于(yu)參考(kao)(kao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)6.9V 時，IC1的(de)6腳輸出低(di)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)平(ping)，T1截(jie)止(zhi)，J1失(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，斷開充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)回(hui)路，實現自動(dong)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)保護功(gong)能(neng)。

當停電(dian)時(shi)，J2失(shi)去(qu)電(dian)源，其動(dong)觸點與(yu)“N/C（常閉點）”接通(tong)，蓄(xu)電(dian)池通(tong)過S1對應急(ji)燈電(dian)路供電(dian)，實現(xian)停電(dian)時(shi)自動(dong)切(qie)換功(gong)能。S1在這里(li)用來手(shou)動(dong)切(qie)斷應急(ji)燈電(dian)路部(bu)分。

制作時，X1選用次級為6V/200mA的電源變壓器。J1、J2選用線圈電壓為6V的繼電器。其他器件選擇可參考圖示，無特殊要求。電路調試很簡單，接 通主電源電時，J2應該動作，LED1為電源指示。然后測量IC1的3腳電壓是否為6.9V左右，之后可用一個外接電源接入IC2腳來調整充電保護電路。 當輸入電壓大于6.9V時，J1應該動作斷開。短開S1，用外接電源接入應急燈電路，測量IC2的輸出是否50Hz，然后可測量X2輸出部分電壓是否為 220V左右既可。LED3為停電/應急燈工作。