一、電壓表是不是內阻越大越好

電壓表內阻(zu)越大越好，主(zhu)要原(yuan)因有以下：

1、因為(wei)開(kai)路電(dian)壓(ya)測量(liang)(liang)要求(qiu)測量(liang)(liang)儀器(qi)的加入不影響(xiang)信號的原式狀(zhuang)態,如果電(dian)壓(ya)表內(nei)阻不夠大(da),就會引起開(kai)路電(dian)壓(ya)發生變化,造成測量(liang)(liang)結果的不正確。所以盡量(liang)(liang)選擇(ze)內(nei)阻為(wei)無窮大(da)的電(dian)壓(ya)表測量(liang)(liang)。

2、電(dian)(dian)壓(ya)(ya)(ya)表(biao)的內阻(zu)越(yue)大越(yue)好，因為(wei)在測(ce)電(dian)(dian)壓(ya)(ya)(ya)時(shi)，電(dian)(dian)壓(ya)(ya)(ya)表(biao)是與(yu)被測(ce)部分(fen)并(bing)聯的。當(dang)電(dian)(dian)壓(ya)(ya)(ya)表(biao)的內阻(zu)越(yue)大時(shi)，則并(bing)聯后的總電(dian)(dian)阻(zu)與(yu)被測(ce)體的本身(shen)的電(dian)(dian)阻(zu)越(yue)接近，則回路電(dian)(dian)流越(yue)接近真實(shi)值，或(huo)者說電(dian)(dian)壓(ya)(ya)(ya)表(biao)分(fen)流越(yue)小越(yue)準確(que)，測(ce)的結果也就越(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(dian)(dian)壓(ya)表可以用來(lai)測(ce)量電(dian)(dian)壓(ya)，當電(dian)(dian)壓(ya)表并聯在電(dian)(dian)路當中時(shi)，會(hui)被這個串聯的電(dian)(dian)阻所分(fen)擔。那(nei)么，接下來(lai)為(wei)大家介紹電(dian)(dian)壓(ya)表串聯在電(dian)(dian)路中會(hui)怎么樣。

會(hui)出現(xian)斷路現(xian)象，數值會(hui)出現(xian)0。在使(shi)用(yong)電(dian)壓表(biao)(biao)時，要(yao)先根據測量(liang)大(da)(da)小選擇合適的量(liang)程，然(ran)后進行(xing)接線(xian)，要(yao)是電(dian)壓表(biao)(biao)接錯，出現(xian)串聯，那會(hui)因內阻太大(da)(da)，使(shi)得測量(liang)電(dian)路出現(xian)開路狀態，這樣電(dian)壓表(biao)(biao)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

所謂的(de)去源法(fa)，簡(jian)單(dan)說法(fa)就是用手捂住電(dian)源，主要看電(dian)壓表與哪(na)部(bu)分構成閉合回路(lu)(lu)，就可以清晰看出電(dian)壓表測的(de)是哪(na)部(bu)分電(dian)路(lu)(lu)的(de)電(dian)壓了。

2、滑線法

電(dian)(dian)(dian)壓(ya)表(biao)的(de)兩(liang)端沿著(zhu)連接的(de)導線滑(hua)動到(dao)耗電(dian)(dian)(dian)元件或電(dian)(dian)(dian)源的(de)兩(liang)端（可(ke)以(yi)跨(kua)越組件：開關、電(dian)(dian)(dian)流表(biao)）。不要交叉(cha)組件：電(dian)(dian)(dian)源、電(dian)(dian)(dian)器、電(dian)(dian)(dian)壓(ya)表(biao)。）滑(hua)動以(yi)查(cha)看電(dian)(dian)(dian)壓(ya)表(biao)測得(de)的(de)電(dian)(dian)(dian)壓(ya)是(shi)否為電(dian)(dian)(dian)源電(dian)(dian)(dian)壓(ya)。

3、短路法

假設導線連(lian)接到此位(wei)置，則電(dian)(dian)壓表被拆下。如果此時某些耗電(dian)(dian)元(yuan)件(jian)或電(dian)(dian)源短路，則這些耗電(dian)(dian)元(yuan)件(jian)或電(dian)(dian)源是電(dian)(dian)壓表的測(ce)量對象。

四、電壓表的工作原理是什么

傳(chuan)統的(de)指針(zhen)式電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)表(biao)(biao)(biao)和(he)電(dian)(dian)(dian)(dian)(dian)流(liu)表(biao)(biao)(biao)都是(shi)根據一個(ge)原理就是(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)的(de)磁效應。電(dian)(dian)(dian)(dian)(dian)流(liu)越(yue)大，所產生的(de)磁力(li)越(yue)大，表(biao)(biao)(biao)現出的(de)就是(shi)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)表(biao)(biao)(biao)上的(de)指針(zhen)的(de)擺幅越(yue)大，電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)表(biao)(biao)(biao)內有一個(ge)磁鐵和(he)一個(ge)導線線圈(quan)，通過電(dian)(dian)(dian)(dian)(dian)流(liu)后(hou)，會(hui)使線圈(quan)產生磁場，線圈(quan)通電(dian)(dian)(dian)(dian)(dian)后(hou)在(zai)磁鐵的(de)作(zuo)用下(xia)會(hui)發生偏轉，這就是(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)表(biao)(biao)(biao)、電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)表(biao)(biao)(biao)的(de)表(biao)(biao)(biao)頭部分。

由于電(dian)(dian)(dian)(dian)壓表要與被測電(dian)(dian)(dian)(dian)阻并(bing)(bing)聯(lian)(lian)，所(suo)(suo)(suo)以(yi)如果直(zhi)接用靈(ling)敏電(dian)(dian)(dian)(dian)流計當電(dian)(dian)(dian)(dian)壓表用，表中(zhong)的(de)電(dian)(dian)(dian)(dian)流過(guo)大，會燒壞電(dian)(dian)(dian)(dian)表，這時(shi)需(xu)要在電(dian)(dian)(dian)(dian)壓表的(de)內部電(dian)(dian)(dian)(dian)路(lu)中(zhong)串聯(lian)(lian)一個(ge)很大的(de)電(dian)(dian)(dian)(dian)阻，這樣改造后(hou)，當電(dian)(dian)(dian)(dian)壓表再(zai)并(bing)(bing)聯(lian)(lian)在電(dian)(dian)(dian)(dian)路(lu)中(zhong)時(shi)，由于電(dian)(dian)(dian)(dian)阻的(de)作(zuo)用，加在電(dian)(dian)(dian)(dian)表兩端的(de)電(dian)(dian)(dian)(dian)壓絕(jue)大部分都被這個(ge)串聯(lian)(lian)的(de)電(dian)(dian)(dian)(dian)阻分擔了，所(suo)(suo)(suo)以(yi)通過(guo)電(dian)(dian)(dian)(dian)表的(de)電(dian)(dian)(dian)(dian)流實際上很小，所(suo)(suo)(suo)以(yi)就可以(yi)正常使用了。