常(chang)見(jian)萬用表的(de)使用和保養
萬(wan)用(yong)(yong)(yong)(yong)表(biao)的(de)(de)(de)(de)結(jie)構形式有很多,面板上(shang)的(de)(de)(de)(de)旋(xuan)(xuan)(xuan)(xuan)鈕、開關的(de)(de)(de)(de)布局各異,因此在使(shi)(shi)用(yong)(yong)(yong)(yong)萬(wan)用(yong)(yong)(yong)(yong)表(biao)之前,應(ying)(ying)仔(zi)細了解和熟悉各部(bu)件的(de)(de)(de)(de)作用(yong)(yong)(yong)(yong),同時(shi)也(ye)要(yao)(yao)分(fen)清(qing)盤上(shang)各條標度尺(chi)所對(dui)(dui)(dui)應(ying)(ying)的(de)(de)(de)(de)測(ce)(ce)t的(de)(de)(de)(de)t。要(yao)(yao)特別注(zhu)意(yi)萬(wan)用(yong)(yong)(yong)(yong)表(biao)的(de)(de)(de)(de)正確使(shi)(shi)用(yong)(yong)(yong)(yong),因為萬(wan)用(yong)(yong)(yong)(yong)表(biao)的(de)(de)(de)(de)故障絕大部(bu)分(fen)是由于操作使(shi)(shi)用(yong)(yong)(yong)(yong)不當而引起的(de)(de)(de)(de).所以(yi)正確使(shi)(shi)用(yong)(yong)(yong)(yong)萬(wan)用(yong)(yong)(yong)(yong)表(biao),實(shi)際上(shang)就是對(dui)(dui)(dui)萬(wan)用(yong)(yong)(yong)(yong)表(biao)最(zui)好(hao)的(de)(de)(de)(de)維護。另外,也(ye)只(zhi)有正確使(shi)(shi)用(yong)(yong)(yong)(yong)萬(wan)用(yong)(yong)(yong)(yong)表(biao).才能使(shi)(shi)測(ce)(ce)t誤差(cha)減小到(dao)最(zui)低程度。萬(wan)用(yong)(yong)(yong)(yong)表(biao)在使(shi)(shi)用(yong)(yong)(yong)(yong)之前應(ying)(ying)水平(ping)放置(zhi),并檢查指(zhi)針是否在零(ling)位(wei),若不在零(ling)位(wei),則應(ying)(ying)調(diao)整萬(wan)用(yong)(yong)(yong)(yong)表(biao)中間(jian)的(de)(de)(de)(de)機械(xie)零(ling)位(wei)調(diao)節螺釘,使(shi)(shi)表(biao)針指(zhi)向(xiang)零(ling)位(wei)。要(yao)(yao)將紅色(se)(se)(se)測(ce)(ce)試(shi)棒(bang)的(de)(de)(de)(de)連接(jie)線接(jie)到(dao)紅色(se)(se)(se)接(jie)線柱(zhu)或標有“+”號的(de)(de)(de)(de)插孔(kong)內,黑(hei)色(se)(se)(se)測(ce)(ce)試(shi)棒(bang)的(de)(de)(de)(de)連接(jie)線接(jie)到(dao)黑(hei)色(se)(se)(se)接(jie)線柱(zhu)或標有“一(yi)’號的(de)(de)(de)(de)插孔(kong)內。要(yao)(yao)根據測(ce)(ce)t的(de)(de)(de)(de)對(dui)(dui)(dui)象將轉換開關旋(xuan)(xuan)(xuan)(xuan)到(dao)孺要(yao)(yao)的(de)(de)(de)(de)位(wei)置(zhi)。例如,測(ce)(ce)t交流電壓(ya)時(shi),應(ying)(ying)將轉換開關旋(xuan)(xuan)(xuan)(xuan)到(dao)相(xiang)應(ying)(ying)區間(jian)上(shang)。有的(de)(de)(de)(de)萬(wan)用(yong)(yong)(yong)(yong)表(biao)盤上(shang)種(zhong)類(lei)選擇(ze)旋(xuan)(xuan)(xuan)(xuan)鈕和t限(xian)變換旋(xuan)(xuan)(xuan)(xuan)鈕分(fen)設。使(shi)(shi)用(yong)(yong)(yong)(yong)時(shi)。應(ying)(ying)先將種(zhong)類(lei)選擇(ze)旋(xuan)(xuan)(xuan)(xuan)鈕旋(xuan)(xuan)(xuan)(xuan)到(dao)對(dui)(dui)(dui)應(ying)(ying)被測(ce)(ce),所需的(de)(de)(de)(de)檔(dang)位(wei),然后再(zai)將t限(xian)變換旋(xuan)(xuan)(xuan)(xuan)鈕旋(xuan)(xuan)(xuan)(xuan)到(dao)相(xiang)應(ying)(ying)檔(dang)位(wei),適(shi)當的(de)(de)(de)(de)t限(xian)。要(yao)(yao)特別注(zhu)意(yi)種(zhong)類(lei)的(de)(de)(de)(de)選擇(ze),否則可能引起嚴重后果。
注意事項
(1)禁(jin)止在雷電時或(huo)高壓設(she)備(bei)附近測(ce)絕緣(yuan)電阻,只能(neng)在設(she)備(bei)不帶電,也沒有感(gan)應電的情況下測(ce)量(liang)。
(2)搖測(ce)過程中,被測(ce)設備上(shang)不能有(you)人工作。
(3)搖(yao)表(biao)線(xian)不能絞在一起,要分開。
(4)搖表未停(ting)止(zhi)轉動之前(qian)或被測設備未放電之前(qian),嚴禁用(yong)手觸及。拆(chai)線時,也(ye)不要(yao)觸及引線的金屬部分(fen)。
(5)測量結束時,對于(yu)大電(dian)(dian)容設備要(yao)放電(dian)(dian)。
(6)要定(ding)期校驗其準確度。