一、功率表和功率因數表區別

功(gong)率因數指有功(gong)功(gong)率和視在功(gong)率的比值(zhi)，一般用(yong)符(fu)號λ表(biao)示，即：λ=P/S。在正弦交(jiao)流(liu)電路中，功(gong)率因數等于電壓與電流(liu)之間的相位差（ψ）的余弦值(zhi)，用(yong)符(fu)號COSψ表(biao)示。此時，COSψ=λ。

功率因(yin)數(shu)(shu)表(biao)(biao)是指單相(xiang)交流(liu)電(dian)路(lu)或電(dian)壓對稱負載平衡的(de)三相(xiang)交流(liu)電(dian)路(lu)中測量(liang)功率因(yin)數(shu)(shu)的(de)儀(yi)表(biao)(biao)。常見的(de)功率因(yin)數(shu)(shu)表(biao)(biao)有電(dian)動系(xi)、鐵磁(ci)電(dian)動系(xi)、電(dian)磁(ci)系(xi)和變換器式等幾種。

功率表也叫瓦特表(biao)，是(shi)一(yi)種測(ce)量(liang)電功(gong)(gong)率(lv)(lv)的儀器。電功(gong)(gong)率(lv)(lv)包括有(you)功(gong)(gong)功(gong)(gong)率(lv)(lv)、無(wu)功(gong)(gong)功(gong)(gong)率(lv)(lv)和視在功(gong)(gong)率(lv)(lv)。未(wei)作特殊說明時，功(gong)(gong)率(lv)(lv)表(biao)一(yi)般是(shi)指(zhi)測(ce)量(liang)有(you)功(gong)(gong)功(gong)(gong)率(lv)(lv)的儀表(biao)。

二、功率因數表能替代功率表嗎

功率因數表(biao)不能替代功率表(biao)，它們有著不同的功能和應(ying)用(yong)場景(jing)。

功(gong)(gong)率(lv)(lv)因(yin)(yin)數表(biao)只測(ce)量(liang)功(gong)(gong)率(lv)(lv)因(yin)(yin)數和其(qi)他電氣參(can)數，不能直接測(ce)量(liang)實(shi)際功(gong)(gong)率(lv)(lv)和其(qi)他功(gong)(gong)率(lv)(lv)值。而功(gong)(gong)率(lv)(lv)表(biao)則可以同時測(ce)量(liang)實(shi)際功(gong)(gong)率(lv)(lv)、有(you)功(gong)(gong)功(gong)(gong)率(lv)(lv)、無功(gong)(gong)功(gong)(gong)率(lv)(lv)和視在功(gong)(gong)率(lv)(lv)等多(duo)個參(can)數。

功率因數表和功率表的(de)(de)應(ying)用范圍(wei)也有所不(bu)同(tong)。功(gong)率因數表(biao)主要(yao)用于(yu)(yu)測(ce)量(liang)電路(lu)中的(de)(de)功(gong)率因數，通常(chang)應(ying)用于(yu)(yu)檢(jian)測(ce)電路(lu)中的(de)(de)無(wu)功(gong)功(gong)率和(he)功(gong)率因數等參數，以優化電路(lu)負載和(he)提高電能利用效(xiao)率。功(gong)率表(biao)則(ze)可(ke)用于(yu)(yu)測(ce)量(liang)電路(lu)中各種功(gong)率值，廣泛應(ying)用于(yu)(yu)家庭、工業、商業等領域中的(de)(de)電力監測(ce)和(he)控(kong)制。

三、功率因數和功率的關系

功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)和(he)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)的(de)(de)關系是：功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)=有功(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)/視(shi)在(zai)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)。功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)是有功(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)與視(shi)在(zai)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)的(de)(de)比值，它的(de)(de)大(da)小(xiao)與電路(lu)的(de)(de)負載性質有關。對于電感(gan)設備比如(ru)電動機(ji)等，功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)小(xiao)于1。有功(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)和(he)功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)的(de)(de)關系可以用(yong)公式P=UIcosφ表示(shi)，其中cosφ就是功(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)因(yin)(yin)數(shu)。