空調電路板常見故障維修方法
1、電源電路
(1)如果空調電路板電源電路(lu)(lu)出現(xian)問(wen)題(ti)(ti),會(hui)以保險管燒毀的形式表現(xian)出來,直接顯示電路(lu)(lu)出現(xian)短路(lu)(lu)問(wen)題(ti)(ti)。
(2)可以使用(yong)萬用(yong)表歐姆擋進行(xing)阻值檢測,并(bing)判斷電路的(de)短(duan)路部位(wei),等找到短(duan)路部位(wei)后(hou),及時進行(xing)更換和修理。
2、感溫電路
(1)當熱敏電(dian)阻(zu)的溫(wen)度(du)越(yue)(yue)低,電(dian)阻(zu)就越(yue)(yue)大;反之(zhi)溫(wen)度(du)越(yue)(yue)高,電(dian)阻(zu)越(yue)(yue)小;25度(du)的阻(zu)值約(yue)在(zai)5-20KΩ左右。
(2)可以用(yong)萬用(yong)表(biao)歐姆擋測(ce)量,如(ru)果所測(ce)量的電(dian)阻(zu)值很小(xiao)或無窮大(da),證明熱敏電(dian)阻(zu)已經損壞(huai),需要立即更換。
3、接收電路
(1)直接用(yong)萬用(yong)表直流擋(dang)測量(liang)接收頭(tou)供(gong)電(dian)(dian)端(duan)、及信(xin)號(hao)端(duan)對地電(dian)(dian)壓,正常的(de)供(gong)電(dian)(dian)極數值(zhi)是+5伏電(dian)(dian)壓,信(xin)號(hao)極電(dian)(dian)壓是+2.5伏。
(2)若數值不對,應(ying)該是接收頭損壞或電容擊穿了,先逐個(ge)排除,然后(hou)找(zhao)到(dao)具體的(de)維修方(fang)法(fa)。
4、晶振電路
(1)空調通(tong)電(dian)開(kai)機后,用(yong)萬用(yong)表測量石英晶振管的兩腳電(dian)壓,數值(zhi)在+2.2伏左右;若小于(yu)1.5伏,電(dian)路有停振問(wen)題(ti)。
(2)可以拆下石(shi)英(ying)(ying)晶振管,用萬用表(biao)歐姆擋進行判斷,顯示開路,說明(ming)石(shi)英(ying)(ying)晶振管是好的;如果是短路,晶體(ti)已經損壞了(le)。
4、CPU故障
電(dian)路板CPU正(zheng)常工(gong)作(zuo)(zuo)的必要條件為:電(dian)源電(dian)壓+5V、復位電(dian)壓、時鐘脈沖信(xin)號,這三(san)個條件缺(que)一不可(ke),否則CPU就不能(neng)正(zheng)常工(gong)作(zuo)(zuo)。所(suo)以,可(ke)用(yong)萬用(yong)表(biao)檢測其工(gong)作(zuo)(zuo)條件的電(dian)壓,若電(dian)壓值正(zheng)常,整機不工(gong)作(zuo)(zuo),即(ji)(ji)可(ke)判(pan)斷CPU芯片(pian)損壞。當(dang)CPU出現故障時,只需更(geng)換CPU即(ji)(ji)可(ke)。
空調電路板維修注意事項
1、對于空調電路板維修我(wo)們要(yao)注(zhu)意的問題有很(hen)多,首先(xian)我(wo)們就先(xian)來了解導線(xian)(xian)(xian)寬(kuan)度(du)這方面所要(yao)注(zhu)意的相關(guan)事項。由于它瞬變電(dian)(dian)流在PCB電(dian)(dian)路板印(yin)制(zhi)(zhi)線(xian)(xian)(xian)條(tiao)上所產生的沖擊干擾,主要(yao)是由印(yin)制(zhi)(zhi)導線(xian)(xian)(xian)的電(dian)(dian)感成分(fen)造成的,因(yin)此應(ying)盡量減(jian)小印(yin)制(zhi)(zhi)導線(xian)(xian)(xian)的電(dian)(dian)感量。采(cai)用正(zheng)確的布(bu)(bu)線(xian)(xian)(xian)策略采(cai)用平等(deng)走線(xian)(xian)(xian)可以(yi)減(jian)少(shao)導線(xian)(xian)(xian)電(dian)(dian)感,但導線(xian)(xian)(xian)之間的互感和分(fen)布(bu)(bu)電(dian)(dian)容增加。如果布(bu)(bu)局允許(xu)最好采(cai)用井字形網(wang)狀布(bu)(bu)線(xian)(xian)(xian)結構,具體做法是印(yin)制(zhi)(zhi)板的一(yi)面橫向(xiang)布(bu)(bu)線(xian)(xian)(xian),另一(yi)面縱向(xiang)布(bu)(bu)線(xian)(xian)(xian),然后在交叉孔(kong)(kong)處(chu)用金屬(shu)化孔(kong)(kong)相連(lian)。
2、由于PCB電路板導線(xian)(xian)它們之(zhi)間(jian)會造(zao)成一些(xie)串(chuan)擾(rao)(rao)問(wen)題,所(suo)以為(wei)了(le)抑制(zhi)這種事情的(de)(de)(de)發生,則(ze)進(jin)行設計(ji)布線(xian)(xian)的(de)(de)(de)時候,應該盡量避免長距離(li)的(de)(de)(de)平等(deng)走線(xian)(xian),盡可能拉(la)開線(xian)(xian)與(yu)線(xian)(xian)之(zhi)間(jian)的(de)(de)(de)距離(li)。信號(hao)線(xian)(xian)與(yu)地(di)線(xian)(xian)及(ji)電源線(xian)(xian)盡可能不交叉,在一些(xie)對干擾(rao)(rao)十分敏(min)感的(de)(de)(de)信號(hao)線(xian)(xian)之(zhi)間(jian)設置一根接地(di)的(de)(de)(de)印制(zhi)線(xian)(xian),可以有(you)效地(di)抑制(zhi)串(chuan)擾(rao)(rao)。
3、在實(shi)際(ji)空調器電(dian)(dian)(dian)腦(nao)板(ban)的(de)(de)故障維修中,應本著先(xian)易后難的(de)(de)原則,先(xian)查電(dian)(dian)(dian)源(yuan)電(dian)(dian)(dian)路和復位電(dian)(dian)(dian)路,然后更換晶振,再(zai)是檢(jian)查搖控(kong)接收電(dian)(dian)(dian)路,最(zui)后才考濾更換CPU。因為(wei)CPU管腳多(duo)更換最(zui)難且(qie)價格(ge)高,更重要(yao)的(de)(de)是CPU損(sun)壞機率相當低,因此不要(yao)輕易更換微(wei)電(dian)(dian)(dian)腦(nao)控(kong)制電(dian)(dian)(dian)路中的(de)(de)CPU。