一、三相多功能電力儀表校驗方法
多功能電(dian)力(li)儀表應定期進行校(xiao)驗,保證測(ce)量的(de)準確(que)性,具(ju)體(ti)的(de)校(xiao)驗方法步驟如下:
1、校驗前
(1)查看多功能電力儀表是(shi)否接入儀表(biao)電(dian)(dian)源,有(you)無示(shi)數。若(ruo)無示(shi)數顯示(shi),則(ze)檢(jian)查(cha)電(dian)(dian)源線,控制電(dian)(dian)源回路。
(2)外觀檢查(cha),檢查(cha)是(shi)否有缺角(jiao),看是(shi)否有零件(jian)脫落或損(sun)壞之處,緊固(gu)件(jian)是(shi)否松動,電路連接線是(shi)否開焊等顯示不正(zheng)常情況。
(3)記錄下(xia)該多(duo)功能(neng)電力(li)儀表(biao)(biao)的銘牌,包括(kuo)生產日期、廠(chang)家、精度(du)、出廠(chang)日期、編(bian)號、變比、型(xing)號、天氣情(qing)況、環境(jing)溫度(du)、環境(jing)濕度(du)等。二次回(hui)路清掃檢查,電流(liu)表(biao)(biao)CT,電壓表(biao)(biao)PT,功率(lv)表(biao)(biao)PT/CT二次側回(hui)路清掃,檢查。
2、主要參數校驗過程
(1)原理
次級(ji)線(xian)圈(quan)的(de)額定(ding)電(dian)壓(ya)一般設計為(wei)100V,與其(qi)配套(tao)使(shi)用的(de)交(jiao)流(liu)(liu)電(dian)壓(ya)表量(liang)程(cheng)也(ye)應為(wei)100V,通過變比換(huan)(huan)算(suan)出(chu)一次側線(xian)電(dian)壓(ya)的(de)標準(zhun)值。次級(ji)線(xian)圈(quan)的(de)額定(ding)電(dian)流(liu)(liu)一般設計為(wei)5A,與其(qi)配套(tao)使(shi)用的(de)交(jiao)流(liu)(liu)電(dian)流(liu)(liu)表量(liang)程(cheng)也(ye)應為(wei)5A,通過變比換(huan)(huan)算(suan)出(chu)一次側相電(dian)流(liu)(liu)的(de)標準(zhun)值,然后根(gen)據電(dian)流(liu)(liu)電(dian)壓(ya),換(huan)(huan)算(suan)出(chu)有功功率(lv),無(wu)功功率(lv)等。
(2)電壓校驗
按照多(duo)(duo)功(gong)能電(dian)(dian)(dian)(dian)(dian)力(li)(li)儀表(biao)說(shuo)明書正(zheng)確設置(zhi)儀表(biao)參數(shu)(shu),在(zai)校驗裝(zhuang)置(zhi)上(shang)輸入(ru)”11.547U”然(ran)后按“Enter”鍵,則此時裝(zhuang)置(zhi)對(dui)多(duo)(duo)功(gong)能電(dian)(dian)(dian)(dian)(dian)力(li)(li)儀表(biao)ABC三相輸入(ru)11.547V相電(dian)(dian)(dian)(dian)(dian)壓,二次線(xian)電(dian)(dian)(dian)(dian)(dian)壓為(wei)20V。操(cao)作多(duo)(duo)功(gong)能電(dian)(dian)(dian)(dian)(dian)力(li)(li)儀表(biao)到(dao)電(dian)(dian)(dian)(dian)(dian)壓顯(xian)示(shi)(shi)界面,記錄下多(duo)(duo)功(gong)能電(dian)(dian)(dian)(dian)(dian)力(li)(li)儀表(biao)線(xian)電(dian)(dian)(dian)(dian)(dian)壓顯(xian)示(shi)(shi)數(shu)(shu)據(ju)。然(ran)后按照上(shang)述方法分(fen)別(bie),在(zai)檢測裝(zhuang)置(zhi)輸入(ru)23.094U,34.642U,46.189U,57.737U,記錄多(duo)(duo)功(gong)能電(dian)(dian)(dian)(dian)(dian)力(li)(li)儀表(biao)線(xian)電(dian)(dian)(dian)(dian)(dian)壓顯(xian)示(shi)(shi)數(shu)(shu)據(ju)。
(3)電流校驗
檢測裝置上先(xian)按(an)(an)(an)Menu鍵進(jin)入(ru)主菜(cai)單,然(ran)后按(an)(an)(an)“1交流(liu)輸(shu)出“進(jin)入(ru)交流(liu)輸(shu)出界(jie)面,按(an)(an)(an)V/Y鍵,用(yong)于Y型或V型接線方式選擇(ze)(ze),一般多(duo)數(shu)為Y型接法,按(an)(an)(an)IRange量程(cheng)鍵選擇(ze)(ze)合(he)適量程(cheng),一般電(dian)(dian)(dian)流(liu)互感器二次側電(dian)(dian)(dian)流(liu)為5A。輸(shu)入(ru)”1I”然(ran)后按(an)(an)(an)Enter鍵,則此時裝置對(dui)儀(yi)表(biao)ABC三(san)相輸(shu)入(ru)1安培電(dian)(dian)(dian)流(liu),調節多(duo)功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)到電(dian)(dian)(dian)流(liu)顯(xian)示界(jie)面,記(ji)(ji)錄下多(duo)功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)顯(xian)示數(shu)據(ju)。然(ran)后按(an)(an)(an)照(zhao)上述方法,分別(bie)輸(shu)入(ru)2I,3I,4I,5I,記(ji)(ji)錄下多(duo)功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)顯(xian)示數(shu)據(ju)。
(4)有功功率,無功功率,功率因素校驗
A、有功(gong)(gong)功(gong)(gong)率(lv):在檢測(ce)裝置上選擇(ze)好電(dian)壓電(dian)流相對應的量程和接線方(fang)式,輸入57.737U然后按(an)Enter鍵(jian)。按(an)快捷鍵(jian)區“Φ試驗點1.0”,調(diao)(diao)整儀表(biao)(biao)(biao)功(gong)(gong)率(lv)為(wei)有功(gong)(gong)功(gong)(gong)率(lv)模式,輸入”1I”然后按(an)Enter鍵(jian),則此時裝置對多(duo)功(gong)(gong)能(neng)電(dian)力(li)儀表(biao)(biao)(biao)ABC三相輸入1安培電(dian)流,線電(dian)壓100V。調(diao)(diao)節多(duo)功(gong)(gong)能(neng)電(dian)力(li)儀表(biao)(biao)(biao)到(dao)有功(gong)(gong)功(gong)(gong)率(lv)顯(xian)示界面,記錄(lu)下(xia)數據。然后按(an)照上述(shu)方(fang)法,分別輸入2I,3I,4I,5I,記錄(lu)下(xia)數據。
B、無(wu)(wu)功(gong)(gong)功(gong)(gong)率(lv):在(zai)(zai)檢測裝(zhuang)置上(shang)按快捷鍵區“Φ試驗點0.0L”或(huo)“Φ試驗點0.0C”調(diao)整多功(gong)(gong)能電(dian)力(li)儀表功(gong)(gong)率(lv)為無(wu)(wu)功(gong)(gong)功(gong)(gong)率(lv)模式,然后在(zai)(zai)分別輸入1I、2I、3I、4I、5I,調(diao)節多功(gong)(gong)能電(dian)力(li)儀表到(dao)無(wu)(wu)功(gong)(gong)功(gong)(gong)功(gong)(gong)率(lv)顯示界面,記錄下數(shu)據。
C、功(gong)率因素(su)(su):在檢測裝置上(shang)分(fen)別按(an)快捷鍵區“Φ試(shi)(shi)驗(yan)(yan)點(dian)0.0L”、“Φ試(shi)(shi)驗(yan)(yan)點(dian)0.5L”、“試(shi)(shi)驗(yan)(yan)點(dian)1.0”、“Φ試(shi)(shi)驗(yan)(yan)點(dian)0.8C”、“Φ試(shi)(shi)驗(yan)(yan)點(dian)0.5C”、“Φ試(shi)(shi)驗(yan)(yan)點(dian)0.0C”,調節多功(gong)能(neng)電力儀表到(dao)功(gong)率因素(su)(su)顯(xian)示界面,記錄下數(shu)據。
3、校驗后
(1)對電源控(kong)制回路(lu)經行檢(jian)查,由于實驗所斷開(kai)的(de)控(kong)制開(kai)關,拔(ba)掉的(de)熔絲,都(dou)要經行復歸。
(2)對于(yu)直接加線(xian)到多功(gong)能電(dian)力(li)(li)儀(yi)(yi)表上的實驗,實驗后(hou)要注意(yi)復歸(gui)過功(gong)能電(dian)力(li)(li)儀(yi)(yi)表上的原來所脫(tuo)開的導線(xian),保(bao)證接線(xian)正確。
(3)對(dui)于端子排上電(dian)壓,電(dian)流回路(lu)進行檢查,由于實驗所(suo)拆的滑片,導線都(dou)要(yao)經行復歸。
二、多功能電力儀表校驗常見問題及處理方法
多功能(neng)電力儀表(biao)校驗過程中,可能(neng)會遇到一(yi)些問題(ti),下面為(wei)大(da)家介紹一(yi)下這些問題(ti)的處理(li)方法:
1、為了檢(jian)測(ce)儀表回路,一(yi)般情況(kuang)下先(xian)從端子(zi)排(pai)上(shang)進行實(shi)驗(yan)。因此(ci)要注(zhu)意通過變壓器二(er)次側向(xiang)一(yi)次側反向(xiang)送電(dian),必須先(xian)把相對應的電(dian)壓二(er)次側回路斷開(kai)。一(yi)般也要在端子(zi)排(pai)上(shang)把電(dian)流互感器二(er)次測(ce)的回路滑(hua)片脫開(kai)。
2、進行電(dian)壓(ya)(ya)(ya)校驗時,注意電(dian)壓(ya)(ya)(ya)回路是否有電(dian)器元(yuan)件(jian)導致(zhi)所加的電(dian)壓(ya)(ya)(ya)分壓(ya)(ya)(ya),造成數(shu)據(ju)的誤差。
3、若(ruo)端子(zi)排線(xian)路(lu)復雜(za),無法進行試驗,則可以直接把電(dian)(dian)壓,電(dian)(dian)流加在儀表上,應(ying)注(zhu)意要脫(tuo)開外電(dian)(dian)路(lu),所(suo)加電(dian)(dian)壓線(xian)的觸頭應(ying)該保(bao)持(chi)一定間隙,防(fang)止短路(lu)。
4、若發現所測電壓,電流數據有微小波(bo)動時,因(yin)先(xian)(xian)檢查是否(fou)所加(jia)頻率是50Hz,然后先(xian)(xian)把電壓,電流加(jia)到滿(man)量程(cheng),一般情(qing)況(kuang)下可以消除(chu)波(bo)動。
5、若發現所(suo)測的(de)電壓,電流,有(you)功(gong),無功(gong)的(de)值(zhi)與標準值(zhi)有(you)明(ming)顯差異時,因先檢查(cha)是(shi)(shi)否(fou)是(shi)(shi)回(hui)路問題,加錯線或(huo)者相序弄(nong)等,然后在檢查(cha)是(shi)(shi)否(fou)是(shi)(shi)該表變比問題,與之前所(suo)記錄的(de)電壓互感器(qi)、電流互感器(qi)變比,進(jin)(jin)行比較。若設置(zhi)錯誤,則(ze)對多功(gong)能(neng)電力(li)儀表進(jin)(jin)行設置(zhi),設置(zhi)正確后,在進(jin)(jin)行校驗。
6、若(ruo)發現所測電流表,功率表是顯示負(fu)數,則要檢查是否(fou)是所加電流極性錯誤。