通(tong)(tong)常用(yong)普通(tong)(tong)電流(liu)表(biao)測量電流(liu)時,需要(yao)將(jiang)電路切斷停機(ji)后(hou)才能將(jiang)電流(liu)表(biao)接(jie)入進行測量,這(zhe)是很麻煩的(de),有時正常運行的(de)電動機(ji)不允(yun)許這(zhe)樣做(zuo)。此時,使用(yong)鉗形電流(liu)表(biao)就顯得方(fang)便多了,可以在不切斷電路的(de)情(qing)況下來測量電流(liu)。
穿過鐵心的(de)(de)被測電(dian)(dian)路(lu)導線(xian)(xian)就(jiu)成(cheng)為電(dian)(dian)流(liu)互感器的(de)(de)一(yi)次線(xian)(xian)圈(quan)(quan),其中通(tong)(tong)過電(dian)(dian)流(liu)便(bian)(bian)在二次線(xian)(xian)圈(quan)(quan)中感應出電(dian)(dian)流(liu)。從而使二次線(xian)(xian)圈(quan)(quan)相連接的(de)(de)電(dian)(dian)流(liu)表(biao)便(bian)(bian)有(you)指(zhi)示-----測出被測線(xian)(xian)路(lu)的(de)(de)電(dian)(dian)流(liu)。鉗形表(biao)可以通(tong)(tong)過轉換(huan)(huan)開(kai)關(guan)的(de)(de)撥(bo)檔,改換(huan)(huan)不同的(de)(de)量程。但撥(bo)檔時不允許帶電(dian)(dian)進行操(cao)作。鉗形表(biao)一(yi)般準確度不高,通(tong)(tong)常為2.5~5級。為了(le)使用方便(bian)(bian),表(biao)內還有(you)不同量程的(de)(de)轉換(huan)(huan)開(kai)關(guan)供測不同等級電(dian)(dian)流(liu)以及(ji)測量電(dian)(dian)壓的(de)(de)功(gong)能。
小巧輕便(bian)的(de)鉗形(xing)表。
40A/400AAC/DC
400V/600VAC,DC
電(dian)阻(zu)/蜂鳴功能(neng)。
自動關機功能。
數據保持功能。
最大顯示4000計數。
自動回零功能。
設計符(fu)合國際安全(quan)規格IEC61010-1CAT.III300V
用(yong)鉗形電(dian)(dian)(dian)流(liu)(liu)(liu)表檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)流(liu)(liu)(liu)時(shi)(shi),一定要(yao)夾入一根被測(ce)(ce)(ce)導線(電(dian)(dian)(dian)線).夾入兩(liang)根(平行(xing)線)則(ze)(ze)不(bu)能檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)流(liu)(liu)(liu).另(ling)外,使(shi)用(yong)鉗形電(dian)(dian)(dian)流(liu)(liu)(liu)表中(zhong)心(xin)(鐵心(xin))檢(jian)(jian)(jian)測(ce)(ce)(ce)時(shi)(shi),檢(jian)(jian)(jian)測(ce)(ce)(ce)誤差小(xiao).在檢(jian)(jian)(jian)查家電(dian)(dian)(dian)產品的(de)(de)耗電(dian)(dian)(dian)量(liang)時(shi)(shi),使(shi)用(yong)線路分離器比較方便,有的(de)(de)線路分離器可將檢(jian)(jian)(jian)測(ce)(ce)(ce)電(dian)(dian)(dian)流(liu)(liu)(liu)放(fang)大10倍,因此(ci)1A以(yi)下的(de)(de)電(dian)(dian)(dian)流(liu)(liu)(liu)可放(fang)大后再(zai)檢(jian)(jian)(jian)測(ce)(ce)(ce).用(yong)直流(liu)(liu)(liu)鉗形電(dian)(dian)(dian)流(liu)(liu)(liu)表檢(jian)(jian)(jian)測(ce)(ce)(ce)直流(liu)(liu)(liu)電(dian)(dian)(dian)流(liu)(liu)(liu)(DCA)時(shi)(shi),如果(guo)電(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)流(liu)(liu)(liu)向相反(fan),則(ze)(ze)顯示出(chu)負數(shu).可使(shi)用(yong)該功能檢(jian)(jian)(jian)測(ce)(ce)(ce)汽車的(de)(de)蓄電(dian)(dian)(dian)池是充(chong)電(dian)(dian)(dian)狀(zhuang)態還是放(fang)電(dian)(dian)(dian)狀(zhuang)態.
平均(jun)值(zhi)(zhi)(zhi)(zhi)方(fang)式的(de)(de)鉗形電流表(biao)通(tong)過交流檢測(ce),檢測(ce)正弦(xian)波(bo)的(de)(de)平均(jun)值(zhi)(zhi)(zhi)(zhi),并將(jiang)放大1.11倍(正弦(xian)波(bo)交流)之后的(de)(de)值(zhi)(zhi)(zhi)(zhi)作為有效(xiao)值(zhi)(zhi)(zhi)(zhi)顯示出來.波(bo)形率不同的(de)(de)正弦(xian)波(bo)以(yi)外的(de)(de)波(bo)形和歪波(bo)也同樣(yang)放大1.11倍后顯示出來,所以(yi)會(hui)產生指示誤差(cha).因(yin)此檢測(ce)正弦(xian)波(bo)以(yi)外的(de)(de)波(bo)形和歪波(bo)時,請選用可直接測(ce)試(shi)出真有效(xiao)值(zhi)(zhi)(zhi)(zhi)的(de)(de)鉗形電流表(biao).
漏(lou)電(dian)(dian)(dian)(dian)檢(jian)測(ce)與通常(chang)的(de)電(dian)(dian)(dian)(dian)流(liu)檢(jian)測(ce)不(bu)同,兩根(gen)(單相(xiang)(xiang)2線(xian)式(shi))或三根(gen)(單相(xiang)(xiang)3線(xian)式(shi),三相(xiang)(xiang)3線(xian)式(shi))要全部夾住(zhu)。也可(ke)夾住(zhu)接地線(xian)進(jin)行檢(jian)測(ce).在低壓電(dian)(dian)(dian)(dian)路上檢(jian)測(ce)漏(lou)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)的(de)絕(jue)緣管理方法(fa),已成為首要的(de)判斷手(shou)段.自其被(1997年電(dian)(dian)(dian)(dian)氣設(she)備技術標(biao)準(zhun)的(de)修正)確認以來,在不(bu)能(neng)停電(dian)(dian)(dian)(dian)的(de)樓宇(yu)和工廠,便逐(zhu)漸(jian)采用漏(lou)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)鉗表來檢(jian)測(ce).
①進(jin)行電流測量時,被測載流體的(de)位置應放在鉗(qian)口中(zhong)央,以免產生(sheng)誤(wu)差。
②測量(liang)前應估計被測電流的大小(xiao),選擇(ze)合(he)適的量(liang)程,在(zai)不知(zhi)道電流大小(xiao)時,應選擇(ze)最大量(liang)程,再根據指針適當減小(xiao)量(liang)程,但不能在(zai)測量(liang)時轉換量(liang)程。
③為了使讀(du)數準(zhun)確(que),應保持鉗口干凈(jing)無損,如有污垢(gou)時,應用汽(qi)油擦洗干凈(jing)再進行測量(liang)。
④在(zai)測(ce)量(liang)5A以下的電流(liu)時,為了測(ce)量(liang)準確,應該繞圈(quan)測(ce)量(liang)。
⑤鉗形表不能測量裸導線電流,以防觸電和短路。
⑥測量(liang)完后一定要將(jiang)量(liang)程分檔旋鈕放到最大量(liang)程位(wei)置上。