一、功率表是什么意思

功率表也叫瓦(wa)特表，是一種(zhong)測(ce)(ce)量電(dian)(dian)(dian)(dian)(dian)功(gong)(gong)率(lv)的(de)儀器(qi)，它通過多種(zhong)方(fang)法(fa)來(lai)計算出(chu)被測(ce)(ce)元件消耗的(de)電(dian)(dian)(dian)(dian)(dian)能(neng)，并(bing)求出(chu)其(qi)對應(ying)的(de)功(gong)(gong)率(lv)值。功(gong)(gong)率(lv)表可以用(yong)于測(ce)(ce)量交流(liu)電(dian)(dian)(dian)(dian)(dian)路(lu)和直流(liu)電(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)的(de)功(gong)(gong)率(lv)，幫助我(wo)們了解(jie)電(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)各種(zhong)元器(qi)件的(de)工(gong)作(zuo)狀況。在直流(liu)電(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)，功(gong)(gong)率(lv)表會利用(yong)電(dian)(dian)(dian)(dian)(dian)阻式(shi)(shi)、熱敏電(dian)(dian)(dian)(dian)(dian)阻式(shi)(shi)等傳感器(qi)進行(xing)功(gong)(gong)率(lv)測(ce)(ce)量；而在交流(liu)電(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)，功(gong)(gong)率(lv)表則需要(yao)考慮相(xiang)位差等因素，采用(yong)電(dian)(dian)(dian)(dian)(dian)壓電(dian)(dian)(dian)(dian)(dian)流(liu)相(xiang)乘或(huo)者功(gong)(gong)率(lv)積分等方(fang)法(fa)進行(xing)功(gong)(gong)率(lv)計算。

二、功率表測量的是什么功率

功率表測量的是電路中的有功功率。有功功率是指電路中真正的功率消耗，也稱為實際有用功率，如電動機輸出的機械功，或者燈泡發出的光能。有功功率(lv)與電壓和電流的相位差有關。當電壓和電流波形完全相同時，有功功率最大，當相位差為90度時，有功功率為0。

三、功率表可以測量視在功率嗎

功(gong)(gong)率(lv)表(biao)既(ji)可以測(ce)量(liang)(liang)有功(gong)(gong)功(gong)(gong)率(lv)，也(ye)可以測(ce)量(liang)(liang)視(shi)在(zai)(zai)功(gong)(gong)率(lv)。視(shi)在(zai)(zai)功(gong)(gong)率(lv)是指電路中的總功(gong)(gong)率(lv)，包括有功(gong)(gong)功(gong)(gong)率(lv)和(he)無(wu)功(gong)(gong)功(gong)(gong)率(lv)。無(wu)功(gong)(gong)功(gong)(gong)率(lv)是指電路中產生的電磁場能量(liang)(liang)，不能被直接(jie)用于做功(gong)(gong)，但是會(hui)對電路造成影響。

在交流(liu)電路中(zhong)，有功(gong)(gong)功(gong)(gong)率(lv)和視在功(gong)(gong)率(lv)之間存在一定的(de)關(guan)系。它們的(de)比值稱為功(gong)(gong)率(lv)因數，通常用cosθ表示，其中(zhong)θ是電壓和電流(liu)的(de)相(xiang)位差。功(gong)(gong)率(lv)因數越高，表示電路的(de)效率(lv)越高，也(ye)就是說(shuo)，更多的(de)能量被用于做功(gong)(gong)而不是浪費。

四、功率表是怎么測量有功功率的

很簡單，功率表就(jiu)是通過測量電(dian)(dian)(dian)(dian)壓和(he)電(dian)(dian)(dian)(dian)流(liu)來計算(suan)的。電(dian)(dian)(dian)(dian)壓表(biao)示電(dian)(dian)(dian)(dian)路中(zhong)的電(dian)(dian)(dian)(dian)勢差，電(dian)(dian)(dian)(dian)流(liu)表(biao)示電(dian)(dian)(dian)(dian)路中(zhong)電(dian)(dian)(dian)(dian)荷的流(liu)動速(su)度。這兩(liang)個值乘起來就(jiu)可以得到功率。

當然，這(zhe)只是一(yi)般情況。在一(yi)些特殊的電(dian)(dian)路中，比(bi)如(ru)包含電(dian)(dian)容或電(dian)(dian)感的電(dian)(dian)路，電(dian)(dian)壓(ya)和電(dian)(dian)流(liu)可能(neng)存在相位差，這(zhe)時有功功率(lv)就不是電(dian)(dian)壓(ya)和電(dian)(dian)流(liu)的簡單(dan)乘積了。

功(gong)率(lv)表測(ce)量(liang)有(you)功(gong)功(gong)率(lv)的方(fang)法主要有(you)兩種：

1、直接測量法：對于一些低(di)壓小功(gong)(gong)率的(de)電(dian)路(lu)，可(ke)以直接(jie)用(yong)功(gong)(gong)率表測量電(dian)壓和電(dian)流，然后通過計算得到功(gong)(gong)率。

2、間接測量法：對(dui)于一些高壓大(da)功(gong)率的(de)電(dian)(dian)路，需要用電(dian)(dian)流(liu)互感(gan)器(qi)和(he)電(dian)(dian)壓互感(gan)器(qi)來降低(di)電(dian)(dian)壓和(he)電(dian)(dian)流(liu)，再(zai)用功(gong)率表測量(liang)。