一、電流表接線方法
在電學實驗或電路調試中,常用到電流表來測量電流大小,使用電流表時,電流表的接線非常關鍵,一般電流表的接線有三種方法:
1、串聯法
將電(dian)(dian)流(liu)(liu)表(biao)串(chuan)聯在電(dian)(dian)路中,以(yi)測(ce)量(liang)電(dian)(dian)路中的電(dian)(dian)流(liu)(liu)。這種方法(fa)需(xu)要斷開電(dian)(dian)路,將電(dian)(dian)流(liu)(liu)表(biao)的正負(fu)極分(fen)別接入電(dian)(dian)路中間,再接上電(dian)(dian)源。需(xu)要注意電(dian)(dian)流(liu)(liu)表(biao)的額(e)定電(dian)(dian)流(liu)(liu)不能小于電(dian)(dian)路中要測(ce)量(liang)的電(dian)(dian)流(liu)(liu)。
2、并聯法
將(jiang)電(dian)(dian)(dian)流(liu)表并(bing)聯在(zai)電(dian)(dian)(dian)路(lu)中(zhong),以測(ce)量電(dian)(dian)(dian)路(lu)負載中(zhong)的電(dian)(dian)(dian)流(liu)。這種方法(fa)可以在(zai)不斷開電(dian)(dian)(dian)路(lu)的情況下進行測(ce)量。需要(yao)在(zai)電(dian)(dian)(dian)路(lu)上加一(yi)個(ge)電(dian)(dian)(dian)流(liu)計支(zhi)路(lu),并(bing)將(jiang)電(dian)(dian)(dian)流(liu)表的正極與(yu)負載相(xiang)連,將(jiang)負極與(yu)電(dian)(dian)(dian)源相(xiang)連。
3、夾式法
夾(jia)式(shi)電(dian)流表(biao)可以(yi)直接夾(jia)在被測電(dian)路(lu)的導(dao)線上,不(bu)需要斷開(kai)電(dian)路(lu)。但使用(yong)夾(jia)式(shi)電(dian)流表(biao)時需要根據其(qi)額定電(dian)流調整(zheng)被測電(dian)路(lu)的負載(zai)(zai)電(dian)流,以(yi)免(mian)過載(zai)(zai)損(sun)壞電(dian)流表(biao)。
二、電流表接線注意事項
1、接線(xian)的時候需(xu)要(yao)分清(qing)正負極(ji),從(cong)正極(ji)入從(cong)負極(ji)出,不能接反。
2、電流表要和負載串聯。
3、任何情況下都(dou)不能把電流表直接接到電源(yuan)正負極。
三、電流表接線柱接反了會怎么樣
使用電(dian)(dian)流(liu)(liu)(liu)表(biao)時,要(yao)確(que)保電(dian)(dian)流(liu)(liu)(liu)由正接線柱流(liu)(liu)(liu)入,負接線柱流(liu)(liu)(liu)出,如(ru)果電(dian)(dian)流(liu)(liu)(liu)表(biao)的正負接線柱的位置接反了,指針(zhen)會(hui)向(xiang)左偏(pian)轉(zhuan),即反向(xiang)偏(pian)轉(zhuan)。如(ru)果電(dian)(dian)流(liu)(liu)(liu)超出電(dian)(dian)流(liu)(liu)(liu)表(biao)的量程,還會(hui)導致電(dian)(dian)流(liu)(liu)(liu)表(biao)被燒壞。