一、電壓表是不是內阻越大越好
電壓表內(nei)阻越大越好,主要原(yuan)因有(you)以下(xia):
1、因為開路電壓(ya)測(ce)量要求測(ce)量儀器(qi)的(de)加入不影響信(xin)號的(de)原式狀態,如果(guo)電壓(ya)表內阻不夠大,就會引(yin)起開路電壓(ya)發(fa)生變化,造成測(ce)量結果(guo)的(de)不正確(que)。所以盡量選擇(ze)內阻為無窮(qiong)大的(de)電壓(ya)表測(ce)量。
2、電(dian)(dian)壓(ya)表(biao)的內阻(zu)越(yue)(yue)大越(yue)(yue)好,因為在(zai)測(ce)電(dian)(dian)壓(ya)時,電(dian)(dian)壓(ya)表(biao)是(shi)與被測(ce)部(bu)分并聯(lian)的。當電(dian)(dian)壓(ya)表(biao)的內阻(zu)越(yue)(yue)大時,則并聯(lian)后的總電(dian)(dian)阻(zu)與被測(ce)體的本身的電(dian)(dian)阻(zu)越(yue)(yue)接近,則回(hui)路電(dian)(dian)流(liu)越(yue)(yue)接近真實(shi)值,或者說電(dian)(dian)壓(ya)表(biao)分流(liu)越(yue)(yue)小(xiao)越(yue)(yue)準確,測(ce)的結果也就越(yue)(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)壓表(biao)可以用來(lai)(lai)測量電(dian)壓,當電(dian)壓表(biao)并聯(lian)(lian)(lian)在(zai)電(dian)路當中時,會被(bei)這(zhe)個(ge)串聯(lian)(lian)(lian)的電(dian)阻所分(fen)擔。那么,接下來(lai)(lai)為(wei)大(da)家介紹電(dian)壓表(biao)串聯(lian)(lian)(lian)在(zai)電(dian)路中會怎(zen)么樣。
會(hui)出(chu)現(xian)斷路現(xian)象,數值會(hui)出(chu)現(xian)0。在使(shi)用電壓表(biao)時(shi),要(yao)先根據測量大(da)小選擇(ze)合適(shi)的量程,然后進行接線,要(yao)是電壓表(biao)接錯,出(chu)現(xian)串(chuan)聯(lian),那會(hui)因內阻太大(da),使(shi)得測量電路出(chu)現(xian)開(kai)路狀態(tai),這樣電壓表(biao)就沒辦(ban)法正常工作。
三、電壓表怎么看測哪個的電壓
1、去源法
所謂(wei)的(de)(de)去源法(fa),簡單說(shuo)法(fa)就是(shi)用手捂(wu)住電(dian)(dian)源,主要看電(dian)(dian)壓表(biao)與哪(na)部分構成閉合回路,就可以清(qing)晰看出電(dian)(dian)壓表(biao)測的(de)(de)是(shi)哪(na)部分電(dian)(dian)路的(de)(de)電(dian)(dian)壓了。
2、滑線法
電(dian)(dian)壓(ya)(ya)(ya)表的(de)兩端沿著連接的(de)導(dao)線(xian)滑動到耗(hao)電(dian)(dian)元件(jian)或電(dian)(dian)源的(de)兩端(可(ke)以(yi)(yi)跨越(yue)組件(jian):開關、電(dian)(dian)流表)。不(bu)要交叉(cha)組件(jian):電(dian)(dian)源、電(dian)(dian)器、電(dian)(dian)壓(ya)(ya)(ya)表。)滑動以(yi)(yi)查看電(dian)(dian)壓(ya)(ya)(ya)表測得(de)的(de)電(dian)(dian)壓(ya)(ya)(ya)是否為電(dian)(dian)源電(dian)(dian)壓(ya)(ya)(ya)。
3、短路法
假設導線連接(jie)到此位置,則(ze)電(dian)(dian)壓表被拆下。如果此時某些(xie)耗電(dian)(dian)元件或電(dian)(dian)源(yuan)短(duan)路(lu),則(ze)這些(xie)耗電(dian)(dian)元件或電(dian)(dian)源(yuan)是電(dian)(dian)壓表的測量對象。
四、電壓表的工作原理是什么
傳(chuan)統的(de)(de)指(zhi)針式電(dian)壓(ya)(ya)(ya)表(biao)和電(dian)流(liu)表(biao)都是根據一個原理就是電(dian)流(liu)的(de)(de)磁效(xiao)應(ying)。電(dian)流(liu)越大(da),所產(chan)生的(de)(de)磁力越大(da),表(biao)現(xian)出(chu)的(de)(de)就是電(dian)壓(ya)(ya)(ya)表(biao)上的(de)(de)指(zhi)針的(de)(de)擺幅越大(da),電(dian)壓(ya)(ya)(ya)表(biao)內(nei)有(you)一個磁鐵(tie)和一個導線(xian)線(xian)圈,通過電(dian)流(liu)后,會使(shi)線(xian)圈產(chan)生磁場,線(xian)圈通電(dian)后在磁鐵(tie)的(de)(de)作(zuo)用下會發生偏轉,這就是電(dian)流(liu)表(biao)、電(dian)壓(ya)(ya)(ya)表(biao)的(de)(de)表(biao)頭部分(fen)。
由(you)(you)于(yu)電(dian)(dian)(dian)(dian)壓表(biao)(biao)要與(yu)被測電(dian)(dian)(dian)(dian)阻并聯(lian),所(suo)(suo)以如果(guo)直接用靈敏電(dian)(dian)(dian)(dian)流計(ji)當電(dian)(dian)(dian)(dian)壓表(biao)(biao)用,表(biao)(biao)中的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)流過大(da),會燒壞電(dian)(dian)(dian)(dian)表(biao)(biao),這時需要在電(dian)(dian)(dian)(dian)壓表(biao)(biao)的(de)(de)(de)(de)內部電(dian)(dian)(dian)(dian)路中串(chuan)聯(lian)一個很大(da)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)阻,這樣改造后,當電(dian)(dian)(dian)(dian)壓表(biao)(biao)再并聯(lian)在電(dian)(dian)(dian)(dian)路中時,由(you)(you)于(yu)電(dian)(dian)(dian)(dian)阻的(de)(de)(de)(de)作用,加在電(dian)(dian)(dian)(dian)表(biao)(biao)兩(liang)端的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)壓絕大(da)部分都(dou)被這個串(chuan)聯(lian)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)阻分擔了(le),所(suo)(suo)以通過電(dian)(dian)(dian)(dian)表(biao)(biao)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)流實際(ji)上很小,所(suo)(suo)以就(jiu)可以正常(chang)使用了(le)。