一、電壓表是不是內阻越大越好
電壓表內阻越(yue)大越(yue)好,主(zhu)要(yao)原因有以下:
1、因(yin)為開(kai)路(lu)電壓測量要求測量儀器的加入不(bu)影響信號的原式狀態,如(ru)果(guo)電壓表內阻(zu)(zu)不(bu)夠大,就會引起開(kai)路(lu)電壓發生(sheng)變化,造成測量結果(guo)的不(bu)正確。所以盡量選擇內阻(zu)(zu)為無窮(qiong)大的電壓表測量。
2、電(dian)(dian)(dian)(dian)(dian)壓表的(de)內阻(zu)越(yue)(yue)大(da)越(yue)(yue)好,因(yin)為在測電(dian)(dian)(dian)(dian)(dian)壓時(shi),電(dian)(dian)(dian)(dian)(dian)壓表是與(yu)被(bei)測部分并聯的(de)。當(dang)電(dian)(dian)(dian)(dian)(dian)壓表的(de)內阻(zu)越(yue)(yue)大(da)時(shi),則并聯后的(de)總(zong)電(dian)(dian)(dian)(dian)(dian)阻(zu)與(yu)被(bei)測體的(de)本身的(de)電(dian)(dian)(dian)(dian)(dian)阻(zu)越(yue)(yue)接(jie)近(jin),則回路電(dian)(dian)(dian)(dian)(dian)流越(yue)(yue)接(jie)近(jin)真實值,或者說電(dian)(dian)(dian)(dian)(dian)壓表分流越(yue)(yue)小(xiao)越(yue)(yue)準(zhun)確,測的(de)結果(guo)也就(jiu)越(yue)(yue)準(zhun)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)壓表可以用來(lai)測量電(dian)壓,當電(dian)壓表并聯(lian)在電(dian)路當中時,會被(bei)這個串(chuan)聯(lian)的電(dian)阻所(suo)分擔。那么,接下來(lai)為(wei)大(da)家介紹電(dian)壓表串(chuan)聯(lian)在電(dian)路中會怎(zen)么樣。
會出現(xian)斷路(lu)現(xian)象(xiang),數值會出現(xian)0。在使用電壓(ya)表時,要先根據測(ce)量大(da)小(xiao)選擇合適的量程,然后進行接線,要是電壓(ya)表接錯,出現(xian)串聯,那會因(yin)內阻太大(da),使得測(ce)量電路(lu)出現(xian)開(kai)路(lu)狀(zhuang)態,這樣電壓(ya)表就(jiu)沒辦法正常工(gong)作(zuo)。
三、電壓表怎么看測哪個的電壓
1、去源法
所謂(wei)的去源法,簡(jian)單說法就(jiu)是用手(shou)捂(wu)住電(dian)源,主要看電(dian)壓表(biao)與哪(na)(na)部(bu)分構成閉合(he)回路(lu),就(jiu)可以清晰看出電(dian)壓表(biao)測的是哪(na)(na)部(bu)分電(dian)路(lu)的電(dian)壓了。
2、滑線法
電壓(ya)表(biao)的兩端(duan)沿著連接的導(dao)線滑動(dong)到耗電元件(jian)或(huo)電源(yuan)的兩端(duan)(可以跨(kua)越組(zu)件(jian):開關、電流表(biao))。不要交叉組(zu)件(jian):電源(yuan)、電器、電壓(ya)表(biao)。)滑動(dong)以查看電壓(ya)表(biao)測得的電壓(ya)是否為電源(yuan)電壓(ya)。
3、短路法
假設導(dao)線連接(jie)到此位置,則(ze)電(dian)壓表被拆下。如(ru)果此時某些耗(hao)電(dian)元(yuan)件或電(dian)源短(duan)路,則(ze)這些耗(hao)電(dian)元(yuan)件或電(dian)源是電(dian)壓表的測量對象。
四、電壓表的工作原理是什么
傳統的(de)(de)指(zhi)針式(shi)電(dian)(dian)(dian)(dian)壓(ya)表(biao)(biao)和(he)電(dian)(dian)(dian)(dian)流表(biao)(biao)都是(shi)根據一(yi)個(ge)原理就是(shi)電(dian)(dian)(dian)(dian)流的(de)(de)磁(ci)效應(ying)。電(dian)(dian)(dian)(dian)流越大(da),所產生(sheng)的(de)(de)磁(ci)力(li)越大(da),表(biao)(biao)現出(chu)的(de)(de)就是(shi)電(dian)(dian)(dian)(dian)壓(ya)表(biao)(biao)上的(de)(de)指(zhi)針的(de)(de)擺幅越大(da),電(dian)(dian)(dian)(dian)壓(ya)表(biao)(biao)內有一(yi)個(ge)磁(ci)鐵和(he)一(yi)個(ge)導線(xian)(xian)線(xian)(xian)圈(quan),通過(guo)電(dian)(dian)(dian)(dian)流后,會(hui)使線(xian)(xian)圈(quan)產生(sheng)磁(ci)場,線(xian)(xian)圈(quan)通電(dian)(dian)(dian)(dian)后在(zai)磁(ci)鐵的(de)(de)作用下會(hui)發生(sheng)偏(pian)轉,這就是(shi)電(dian)(dian)(dian)(dian)流表(biao)(biao)、電(dian)(dian)(dian)(dian)壓(ya)表(biao)(biao)的(de)(de)表(biao)(biao)頭部分(fen)。
由(you)于電(dian)(dian)(dian)壓(ya)(ya)表(biao)要與(yu)被(bei)測電(dian)(dian)(dian)阻(zu)并聯(lian),所以(yi)如(ru)果直接用靈敏電(dian)(dian)(dian)流計當(dang)(dang)電(dian)(dian)(dian)壓(ya)(ya)表(biao)用,表(biao)中的(de)電(dian)(dian)(dian)流過大(da),會(hui)燒壞電(dian)(dian)(dian)表(biao),這時需要在電(dian)(dian)(dian)壓(ya)(ya)表(biao)的(de)內部電(dian)(dian)(dian)路中串(chuan)聯(lian)一個(ge)很(hen)大(da)的(de)電(dian)(dian)(dian)阻(zu),這樣改(gai)造后,當(dang)(dang)電(dian)(dian)(dian)壓(ya)(ya)表(biao)再并聯(lian)在電(dian)(dian)(dian)路中時,由(you)于電(dian)(dian)(dian)阻(zu)的(de)作(zuo)用,加在電(dian)(dian)(dian)表(biao)兩端的(de)電(dian)(dian)(dian)壓(ya)(ya)絕大(da)部分(fen)都被(bei)這個(ge)串(chuan)聯(lian)的(de)電(dian)(dian)(dian)阻(zu)分(fen)擔了,所以(yi)通過電(dian)(dian)(dian)表(biao)的(de)電(dian)(dian)(dian)流實際(ji)上很(hen)小,所以(yi)就可以(yi)正常(chang)使用了。