一、電壓表是不是內阻越大越好
電(dian)壓(ya)表內阻越大越好,主(zhu)要原因有以下:
1、因(yin)為開路(lu)電壓測(ce)(ce)量(liang)(liang)要(yao)求測(ce)(ce)量(liang)(liang)儀器的(de)加入不(bu)(bu)影響信號(hao)的(de)原式狀態(tai),如果(guo)電壓表內阻不(bu)(bu)夠大,就會引起開路(lu)電壓發生變化,造成測(ce)(ce)量(liang)(liang)結果(guo)的(de)不(bu)(bu)正確。所以盡量(liang)(liang)選擇內阻為無窮大的(de)電壓表測(ce)(ce)量(liang)(liang)。
2、電(dian)(dian)壓表(biao)(biao)的(de)內阻(zu)越(yue)(yue)大(da)越(yue)(yue)好(hao),因為在(zai)測電(dian)(dian)壓時,電(dian)(dian)壓表(biao)(biao)是與(yu)被(bei)測部分并聯的(de)。當電(dian)(dian)壓表(biao)(biao)的(de)內阻(zu)越(yue)(yue)大(da)時,則并聯后的(de)總電(dian)(dian)阻(zu)與(yu)被(bei)測體(ti)的(de)本(ben)身(shen)的(de)電(dian)(dian)阻(zu)越(yue)(yue)接近(jin),則回路電(dian)(dian)流(liu)越(yue)(yue)接近(jin)真實值,或者說電(dian)(dian)壓表(biao)(biao)分流(liu)越(yue)(yue)小越(yue)(yue)準確(que),測的(de)結果(guo)也就越(yue)(yue)準確(que)。
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
電壓表可以用來測(ce)量電壓,當電壓表并聯在電路當中(zhong)時,會(hui)被(bei)這個(ge)串聯的電阻所(suo)分(fen)擔。那么,接下來為(wei)大家介紹電壓表串聯在電路中(zhong)會(hui)怎(zen)么樣(yang)。
會出(chu)(chu)現(xian)斷(duan)路現(xian)象,數值會出(chu)(chu)現(xian)0。在使(shi)用電壓(ya)(ya)表時,要先根據測(ce)量大小選擇合適(shi)的(de)量程,然(ran)后進(jin)行(xing)接線,要是(shi)電壓(ya)(ya)表接錯,出(chu)(chu)現(xian)串聯,那(nei)會因內阻太大,使(shi)得測(ce)量電路出(chu)(chu)現(xian)開路狀(zhuang)態,這(zhe)樣電壓(ya)(ya)表就沒(mei)辦法正(zheng)常工作。
三、電壓表怎么看測哪個的電壓
1、去源法
所(suo)謂的(de)(de)去源(yuan)法(fa)(fa),簡單說法(fa)(fa)就是用(yong)手捂住電(dian)源(yuan),主(zhu)要看電(dian)壓表(biao)與哪(na)部分構成(cheng)閉(bi)合(he)回路,就可以清晰(xi)看出電(dian)壓表(biao)測的(de)(de)是哪(na)部分電(dian)路的(de)(de)電(dian)壓了。
2、滑線法
電(dian)(dian)(dian)壓表(biao)(biao)的(de)兩(liang)(liang)端(duan)沿著(zhu)連接的(de)導線(xian)滑動到耗電(dian)(dian)(dian)元件或(huo)電(dian)(dian)(dian)源的(de)兩(liang)(liang)端(duan)(可以跨越(yue)組件:開(kai)關、電(dian)(dian)(dian)流(liu)表(biao)(biao))。不要交叉組件:電(dian)(dian)(dian)源、電(dian)(dian)(dian)器、電(dian)(dian)(dian)壓表(biao)(biao)。)滑動以查(cha)看電(dian)(dian)(dian)壓表(biao)(biao)測得(de)的(de)電(dian)(dian)(dian)壓是否為電(dian)(dian)(dian)源電(dian)(dian)(dian)壓。
3、短路法
假設導線(xian)連接到此位置,則(ze)電(dian)壓(ya)表被(bei)拆下。如果此時某些(xie)耗(hao)電(dian)元件或(huo)電(dian)源短(duan)路,則(ze)這些(xie)耗(hao)電(dian)元件或(huo)電(dian)源是電(dian)壓(ya)表的測(ce)量對象。
四、電壓表的工作原理是什么
傳統的(de)(de)指針(zhen)(zhen)式電(dian)(dian)(dian)壓(ya)(ya)(ya)表(biao)和電(dian)(dian)(dian)流(liu)(liu)表(biao)都是(shi)根據一(yi)個原理就是(shi)電(dian)(dian)(dian)流(liu)(liu)的(de)(de)磁效(xiao)應(ying)。電(dian)(dian)(dian)流(liu)(liu)越大(da),所產生(sheng)的(de)(de)磁力越大(da),表(biao)現出的(de)(de)就是(shi)電(dian)(dian)(dian)壓(ya)(ya)(ya)表(biao)上的(de)(de)指針(zhen)(zhen)的(de)(de)擺幅越大(da),電(dian)(dian)(dian)壓(ya)(ya)(ya)表(biao)內有一(yi)個磁鐵和一(yi)個導線(xian)線(xian)圈(quan),通過(guo)電(dian)(dian)(dian)流(liu)(liu)后(hou),會(hui)使線(xian)圈(quan)產生(sheng)磁場(chang),線(xian)圈(quan)通電(dian)(dian)(dian)后(hou)在磁鐵的(de)(de)作(zuo)用下會(hui)發生(sheng)偏轉(zhuan),這就是(shi)電(dian)(dian)(dian)流(liu)(liu)表(biao)、電(dian)(dian)(dian)壓(ya)(ya)(ya)表(biao)的(de)(de)表(biao)頭(tou)部分。
由(you)于電(dian)(dian)壓(ya)(ya)(ya)表要(yao)與被(bei)測電(dian)(dian)阻(zu)(zu)并(bing)(bing)聯(lian)(lian),所(suo)以(yi)如果直接用(yong)(yong)靈敏電(dian)(dian)流(liu)計(ji)當電(dian)(dian)壓(ya)(ya)(ya)表用(yong)(yong),表中的(de)電(dian)(dian)流(liu)過大,會(hui)燒(shao)壞電(dian)(dian)表,這(zhe)時(shi)需要(yao)在電(dian)(dian)壓(ya)(ya)(ya)表的(de)內部電(dian)(dian)路(lu)中串(chuan)聯(lian)(lian)一個很大的(de)電(dian)(dian)阻(zu)(zu),這(zhe)樣改(gai)造后,當電(dian)(dian)壓(ya)(ya)(ya)表再并(bing)(bing)聯(lian)(lian)在電(dian)(dian)路(lu)中時(shi),由(you)于電(dian)(dian)阻(zu)(zu)的(de)作用(yong)(yong),加在電(dian)(dian)表兩端的(de)電(dian)(dian)壓(ya)(ya)(ya)絕(jue)大部分都被(bei)這(zhe)個串(chuan)聯(lian)(lian)的(de)電(dian)(dian)阻(zu)(zu)分擔了,所(suo)以(yi)通過電(dian)(dian)表的(de)電(dian)(dian)流(liu)實際上(shang)很小,所(suo)以(yi)就可以(yi)正(zheng)常(chang)使用(yong)(yong)了。