干手機壞了怎么辦
有時候全自(zi)動感應(ying)干手器(qi)指示(shi)燈(deng)不亮,也不工作,應(ying)該重(zhong)點檢(jian)查供電(dian)(dian)(dian)(dian)線(xian)(xian)(xian)路(lu)。打開干手器(qi)外殼,用萬用表檢(jian)測電(dian)(dian)(dian)(dian)源線(xian)(xian)(xian)與(yu)主板(ban)(ban)連(lian)接(jie)處(chu)針腳,看是(shi)(shi)(shi)否(fou)(fou)有正常的電(dian)(dian)(dian)(dian)壓輸(shu)入。如(ru)(ru)果(guo)市電(dian)(dian)(dian)(dian)輸(shu)入正常,就需(xu)要檢(jian)查線(xian)(xian)(xian)路(lu)板(ban)(ban)上是(shi)(shi)(shi)否(fou)(fou)有元件(jian)擊穿,形(xing)成斷路(lu),比如(ru)(ru)整流橋(qiao)、保險絲等(deng)如(ru)(ru)果(guo)沒有電(dian)(dian)(dian)(dian)壓輸(shu)入,需(xu)要檢(jian)查電(dian)(dian)(dian)(dian)源線(xian)(xian)(xian)是(shi)(shi)(shi)否(fou)(fou)有斷線(xian)(xian)(xian),電(dian)(dian)(dian)(dian)源插座是(shi)(shi)(shi)否(fou)(fou)有故障。
噴射式干手機的常見故障
故障現象1:手放入熱風出口,無熱風吹出,只有冷風吹出。
分析檢修:實繪相關電路如圖1所示。有(you)冷風吹(chui)(chui)出,說明吹(chui)(chui)風機電(dian)機得電(dian)工作,紅外檢(jian)測及控制電(dian)路(lu)正常(chang)。只有(you)冷風,說明加熱器(qi)斷(duan)路(lu)或接(jie)線松脫。經檢(jian)查,是加熱器(qi)接(jie)線松動。重接(jie)后,有(you)熱風吹(chui)(chui)出,故障排(pai)除。
故障現象2:上電后,手還沒有放在熱風出口。熱風即失控吹出。
分析檢修:經查,可控(kong)硅無擊穿現(xian)象,懷疑是光(guang)電(dian)耦(ou)合(he)(he)器③、④腳內部光(guang)敏管漏電(dian)擊穿。更換光(guang)電(dian)耦(ou)合(he)(he)器后,工作恢復正常,故障排除。
故障現象3:手放入熱風出口,沒有熱風吹出。
分析檢修:查風機及加熱器正常,測可控硅柵極無觸發電壓,測控制三極管Ⅵ的c極有矩形波信號輸出,懷(huai)疑是光(guang)電耦合器不良e,用(yong)萬用(yong)表Rxl0擋測光(guang)電(dian)耦合器③、④腳間的正(zheng)、反(fan)向電(dian)阻均為(wei)無窮大,正(zheng)常時(shi)正(zheng)向阻值(zhi)應為(wei)數m,反(fan)向(xiang)阻值為(wei)無窮大,判定是內部光(guang)(guang)敏(min)管開(kai)路,導致可控硅柵極得不到觸發電(dian)(dian)壓(ya)而不能(neng)導通。更(geng)換光(guang)(guang)電(dian)(dian)耦合(he)器(qi)后,故障排(pai)除。
故障現象4:通電后指示燈亮,但伸手后無熱風吹出。
分析風機和加熱器同時發生故障的可能性很小,多見為繼電器壞或未動作,而J不動作可(ke)能為(wei)V3不導(dao)通(tong);運放(fang)無輸出;D6、D5失效(xiao);V1、V2未(wei)起振或7812損壞導致無12V電壓。
檢查時先測(ce)有無12V電(dian)壓,若有,伸手試探并測運放⑦腳電(dian)平有無變化(hua)(hua)。有變化(hua)(hua),向(xiang)后(hou)查V3和繼(ji)電器;無變化,向前查運放電路(lu)、光電轉換及振蕩電路(lu)。
故障現象5:通電后指示燈亮,但感應靈敏(min)度低。
此故障除(chu)了運(yun)放(fang)電路(lu)有異常外,多見為紅發射和接(jie)收管被(bei)灰(hui)塵污染所致,清洗即(ji)可。