一、電壓表是不是內阻越大越好
電壓表(biao)內阻(zu)越(yue)大越(yue)好,主要原因有(you)以下(xia):
1、因為開路(lu)電(dian)壓(ya)測(ce)量(liang)要求測(ce)量(liang)儀器(qi)的加入不影(ying)響信號的原式(shi)狀態,如果(guo)(guo)電(dian)壓(ya)表內阻不夠(gou)大,就會引起開路(lu)電(dian)壓(ya)發生變化,造成測(ce)量(liang)結(jie)果(guo)(guo)的不正確。所(suo)以盡量(liang)選擇內阻為無窮大的電(dian)壓(ya)表測(ce)量(liang)。
2、電(dian)(dian)(dian)壓表的(de)(de)內(nei)阻越(yue)大(da)越(yue)好,因為在測(ce)電(dian)(dian)(dian)壓時,電(dian)(dian)(dian)壓表是與被測(ce)部分并聯(lian)的(de)(de)。當(dang)電(dian)(dian)(dian)壓表的(de)(de)內(nei)阻越(yue)大(da)時,則(ze)并聯(lian)后的(de)(de)總電(dian)(dian)(dian)阻與被測(ce)體(ti)的(de)(de)本身的(de)(de)電(dian)(dian)(dian)阻越(yue)接近,則(ze)回(hui)路(lu)電(dian)(dian)(dian)流越(yue)接近真實值,或(huo)者說電(dian)(dian)(dian)壓表分流越(yue)小越(yue)準確,測(ce)的(de)(de)結果(guo)也就越(yue)準確。
可以到電壓表十大品牌了解更多信息哦。
二、電壓表串聯在電路中會怎么樣
電(dian)(dian)壓表(biao)可以用來(lai)測量(liang)電(dian)(dian)壓,當(dang)電(dian)(dian)壓表(biao)并(bing)聯(lian)(lian)在電(dian)(dian)路當(dang)中(zhong)時,會被這(zhe)個串(chuan)聯(lian)(lian)的電(dian)(dian)阻所分擔。那么,接下來(lai)為大(da)家介紹電(dian)(dian)壓表(biao)串(chuan)聯(lian)(lian)在電(dian)(dian)路中(zhong)會怎(zen)么樣。
會(hui)(hui)出(chu)現(xian)(xian)斷路現(xian)(xian)象(xiang),數值會(hui)(hui)出(chu)現(xian)(xian)0。在使用(yong)電(dian)壓(ya)(ya)表時,要先根據測量大小選擇合適的量程,然后進行接線,要是電(dian)壓(ya)(ya)表接錯,出(chu)現(xian)(xian)串(chuan)聯(lian),那會(hui)(hui)因內阻太大,使得測量電(dian)路出(chu)現(xian)(xian)開路狀態,這樣電(dian)壓(ya)(ya)表就沒辦法正常工作。
三、電壓表怎么看測哪個的電壓
1、去源法
所(suo)謂的去源法(fa),簡單說法(fa)就(jiu)是用手捂(wu)住電源,主(zhu)要看電壓表(biao)與哪(na)部分構成閉合回路,就(jiu)可以清晰(xi)看出電壓表(biao)測的是哪(na)部分電路的電壓了。
2、滑線法
電(dian)(dian)壓(ya)(ya)表(biao)的(de)(de)兩端沿(yan)著連(lian)接的(de)(de)導線滑動到耗(hao)電(dian)(dian)元件(jian)或(huo)電(dian)(dian)源的(de)(de)兩端(可以跨越(yue)組件(jian):開關、電(dian)(dian)流表(biao))。不要(yao)交(jiao)叉組件(jian):電(dian)(dian)源、電(dian)(dian)器、電(dian)(dian)壓(ya)(ya)表(biao)。)滑動以查(cha)看電(dian)(dian)壓(ya)(ya)表(biao)測得的(de)(de)電(dian)(dian)壓(ya)(ya)是(shi)否為電(dian)(dian)源電(dian)(dian)壓(ya)(ya)。
3、短路法
假設導線連接到此位置,則(ze)電(dian)壓(ya)(ya)表(biao)被拆下。如(ru)果此時某些耗(hao)電(dian)元(yuan)件或電(dian)源短路,則(ze)這些耗(hao)電(dian)元(yuan)件或電(dian)源是電(dian)壓(ya)(ya)表(biao)的(de)測(ce)量對象。
四、電壓表的工作原理是什么
傳(chuan)統的(de)(de)指(zhi)針式電(dian)(dian)(dian)壓(ya)表和電(dian)(dian)(dian)流表都是根據一(yi)個(ge)原理就是電(dian)(dian)(dian)流的(de)(de)磁效(xiao)應。電(dian)(dian)(dian)流越(yue)大,所(suo)產生(sheng)的(de)(de)磁力越(yue)大,表現出的(de)(de)就是電(dian)(dian)(dian)壓(ya)表上的(de)(de)指(zhi)針的(de)(de)擺幅越(yue)大,電(dian)(dian)(dian)壓(ya)表內有一(yi)個(ge)磁鐵和一(yi)個(ge)導線線圈(quan),通過電(dian)(dian)(dian)流后,會使線圈(quan)產生(sheng)磁場,線圈(quan)通電(dian)(dian)(dian)后在磁鐵的(de)(de)作用下會發生(sheng)偏轉,這就是電(dian)(dian)(dian)流表、電(dian)(dian)(dian)壓(ya)表的(de)(de)表頭部分。
由(you)于電(dian)(dian)(dian)(dian)(dian)(dian)壓表要(yao)與被(bei)測電(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)并聯,所(suo)以如(ru)果直接用(yong)(yong)靈敏電(dian)(dian)(dian)(dian)(dian)(dian)流計當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)壓表用(yong)(yong),表中(zhong)的電(dian)(dian)(dian)(dian)(dian)(dian)流過大(da),會燒(shao)壞電(dian)(dian)(dian)(dian)(dian)(dian)表,這時(shi)需(xu)要(yao)在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)壓表的內部電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)串(chuan)聯一個很大(da)的電(dian)(dian)(dian)(dian)(dian)(dian)阻(zu),這樣改造后,當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)壓表再并聯在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)時(shi),由(you)于電(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)的作用(yong)(yong),加在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)表兩端的電(dian)(dian)(dian)(dian)(dian)(dian)壓絕大(da)部分都被(bei)這個串(chuan)聯的電(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)分擔了,所(suo)以通過電(dian)(dian)(dian)(dian)(dian)(dian)表的電(dian)(dian)(dian)(dian)(dian)(dian)流實際(ji)上很小,所(suo)以就可以正常(chang)使用(yong)(yong)了。