一、三相多功能電力儀表校驗方法
多功能電力(li)儀表應定(ding)期(qi)進(jin)行(xing)校驗,保證(zheng)測量的準(zhun)確性,具(ju)體的校驗方法步驟(zou)如(ru)下:
1、校驗前
(1)查看多功能電力儀表是否接入儀表電(dian)(dian)源,有無示(shi)(shi)數。若無示(shi)(shi)數顯(xian)示(shi)(shi),則檢(jian)查電(dian)(dian)源線,控制(zhi)電(dian)(dian)源回路。
(2)外觀檢查,檢查是(shi)否有(you)缺角,看是(shi)否有(you)零件(jian)脫(tuo)落(luo)或損壞之處(chu),緊固件(jian)是(shi)否松動,電路連接線(xian)是(shi)否開焊等顯示不正常情況。
(3)記錄下(xia)該多功能電力儀表的銘牌,包括生產(chan)日(ri)期、廠家、精度(du)、出廠日(ri)期、編號、變比、型號、天氣(qi)情況、環境(jing)溫度(du)、環境(jing)濕度(du)等(deng)。二次回路(lu)清(qing)掃檢查,電流表CT,電壓表PT,功率表PT/CT二次側回路(lu)清(qing)掃,檢查。
2、主要參數校驗過程
(1)原理
次級線圈(quan)(quan)的額定電(dian)(dian)壓(ya)一(yi)般(ban)設計(ji)為100V,與(yu)(yu)其(qi)配套(tao)使用的交流(liu)電(dian)(dian)壓(ya)表(biao)量程也應為100V,通過變比換算出一(yi)次側線電(dian)(dian)壓(ya)的標準(zhun)值。次級線圈(quan)(quan)的額定電(dian)(dian)流(liu)一(yi)般(ban)設計(ji)為5A,與(yu)(yu)其(qi)配套(tao)使用的交流(liu)電(dian)(dian)流(liu)表(biao)量程也應為5A,通過變比換算出一(yi)次側相(xiang)電(dian)(dian)流(liu)的標準(zhun)值,然后根據電(dian)(dian)流(liu)電(dian)(dian)壓(ya),換算出有功(gong)功(gong)率(lv),無功(gong)功(gong)率(lv)等。
(2)電壓校驗
按(an)照(zhao)多(duo)(duo)(duo)功(gong)(gong)能電(dian)(dian)(dian)力(li)儀(yi)(yi)(yi)表(biao)說明書正(zheng)確(que)設置(zhi)儀(yi)(yi)(yi)表(biao)參(can)數,在校驗(yan)裝(zhuang)置(zhi)上(shang)輸入(ru)”11.547U”然(ran)后(hou)按(an)“Enter”鍵,則此時裝(zhuang)置(zhi)對多(duo)(duo)(duo)功(gong)(gong)能電(dian)(dian)(dian)力(li)儀(yi)(yi)(yi)表(biao)ABC三相輸入(ru)11.547V相電(dian)(dian)(dian)壓(ya)(ya),二(er)次線(xian)電(dian)(dian)(dian)壓(ya)(ya)為20V。操作多(duo)(duo)(duo)功(gong)(gong)能電(dian)(dian)(dian)力(li)儀(yi)(yi)(yi)表(biao)到電(dian)(dian)(dian)壓(ya)(ya)顯示界(jie)面,記錄下多(duo)(duo)(duo)功(gong)(gong)能電(dian)(dian)(dian)力(li)儀(yi)(yi)(yi)表(biao)線(xian)電(dian)(dian)(dian)壓(ya)(ya)顯示數據(ju)。然(ran)后(hou)按(an)照(zhao)上(shang)述方(fang)法(fa)分別,在檢測裝(zhuang)置(zhi)輸入(ru)23.094U,34.642U,46.189U,57.737U,記錄多(duo)(duo)(duo)功(gong)(gong)能電(dian)(dian)(dian)力(li)儀(yi)(yi)(yi)表(biao)線(xian)電(dian)(dian)(dian)壓(ya)(ya)顯示數據(ju)。
(3)電流校驗
檢測裝置(zhi)上先按(an)(an)Menu鍵(jian)進入(ru)(ru)(ru)主菜單,然后按(an)(an)“1交流(liu)輸(shu)出(chu)(chu)“進入(ru)(ru)(ru)交流(liu)輸(shu)出(chu)(chu)界面,按(an)(an)V/Y鍵(jian),用于Y型或(huo)V型接線方(fang)式(shi)選擇(ze),一般(ban)多數(shu)為(wei)Y型接法,按(an)(an)IRange量程(cheng)鍵(jian)選擇(ze)合適量程(cheng),一般(ban)電(dian)(dian)(dian)流(liu)互(hu)感器二次側電(dian)(dian)(dian)流(liu)為(wei)5A。輸(shu)入(ru)(ru)(ru)”1I”然后按(an)(an)Enter鍵(jian),則此時裝置(zhi)對儀(yi)表(biao)ABC三相輸(shu)入(ru)(ru)(ru)1安(an)培(pei)電(dian)(dian)(dian)流(liu),調節多功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)到電(dian)(dian)(dian)流(liu)顯(xian)示(shi)界面,記(ji)(ji)錄下多功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)顯(xian)示(shi)數(shu)據。然后按(an)(an)照上述方(fang)法,分別輸(shu)入(ru)(ru)(ru)2I,3I,4I,5I,記(ji)(ji)錄下多功(gong)能電(dian)(dian)(dian)力儀(yi)表(biao)顯(xian)示(shi)數(shu)據。
(4)有功功率,無功功率,功率因素校驗
A、有功(gong)功(gong)率(lv):在(zai)檢測裝(zhuang)置上選擇(ze)好電(dian)壓(ya)電(dian)流相對(dui)應(ying)的量程和接線(xian)方式,輸入(ru)57.737U然后(hou)按(an)(an)Enter鍵。按(an)(an)快(kuai)捷鍵區“Φ試驗點(dian)1.0”,調(diao)整(zheng)儀(yi)表(biao)功(gong)率(lv)為有功(gong)功(gong)率(lv)模(mo)式,輸入(ru)”1I”然后(hou)按(an)(an)Enter鍵,則此時(shi)裝(zhuang)置對(dui)多功(gong)能電(dian)力(li)儀(yi)表(biao)ABC三相輸入(ru)1安(an)培(pei)電(dian)流,線(xian)電(dian)壓(ya)100V。調(diao)節多功(gong)能電(dian)力(li)儀(yi)表(biao)到有功(gong)功(gong)率(lv)顯(xian)示界面(mian),記錄(lu)下數(shu)據。然后(hou)按(an)(an)照上述方法,分別輸入(ru)2I,3I,4I,5I,記錄(lu)下數(shu)據。
B、無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)率(lv):在檢測裝置(zhi)上(shang)按快捷鍵區“Φ試驗點(dian)0.0L”或“Φ試驗點(dian)0.0C”調整多功(gong)(gong)(gong)能(neng)電力(li)儀(yi)表功(gong)(gong)(gong)率(lv)為(wei)無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)率(lv)模式,然后在分(fen)別輸入(ru)1I、2I、3I、4I、5I,調節多功(gong)(gong)(gong)能(neng)電力(li)儀(yi)表到(dao)無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)功(gong)(gong)(gong)率(lv)顯(xian)示界面,記(ji)錄下數據。
C、功率因(yin)素(su):在檢測裝(zhuang)置(zhi)上(shang)分別按快捷(jie)鍵區“Φ試(shi)(shi)驗(yan)點(dian)0.0L”、“Φ試(shi)(shi)驗(yan)點(dian)0.5L”、“試(shi)(shi)驗(yan)點(dian)1.0”、“Φ試(shi)(shi)驗(yan)點(dian)0.8C”、“Φ試(shi)(shi)驗(yan)點(dian)0.5C”、“Φ試(shi)(shi)驗(yan)點(dian)0.0C”,調節多(duo)功能(neng)電力(li)儀表到功率因(yin)素(su)顯(xian)示界面,記(ji)錄(lu)下(xia)數據。
3、校驗后
(1)對電源控制(zhi)回路經行檢(jian)查(cha),由于實驗所(suo)斷開的控制(zhi)開關(guan),拔掉的熔絲,都要經行復歸。
(2)對(dui)于直(zhi)接(jie)加(jia)線(xian)到多功(gong)能(neng)電(dian)力儀表(biao)上(shang)的(de)(de)(de)實驗(yan),實驗(yan)后要注意復(fu)歸(gui)過功(gong)能(neng)電(dian)力儀表(biao)上(shang)的(de)(de)(de)原來所脫開的(de)(de)(de)導線(xian),保證接(jie)線(xian)正確。
(3)對于(yu)端子排上電(dian)壓,電(dian)流回路(lu)進行(xing)檢(jian)查,由于(yu)實(shi)驗所拆的滑片(pian),導線(xian)都要經行(xing)復歸。
二、多功能電力儀表校驗常見問題及處理方法
多(duo)功能電力儀表校驗過程(cheng)中,可能會(hui)遇(yu)到一些問題,下面為大家介紹一下這些問題的處理方法:
1、為了檢測(ce)(ce)儀表回路(lu),一(yi)般(ban)情況下先(xian)從端(duan)(duan)子(zi)排(pai)上進行實(shi)驗。因此(ci)要注意(yi)通過(guo)變壓器二次(ci)側向一(yi)次(ci)側反向送(song)電(dian),必須先(xian)把相對應的電(dian)壓二次(ci)側回路(lu)斷(duan)開。一(yi)般(ban)也(ye)要在端(duan)(duan)子(zi)排(pai)上把電(dian)流互感器二次(ci)測(ce)(ce)的回路(lu)滑片(pian)脫開。
2、進(jin)行電壓校驗時,注意電壓回(hui)路是否有(you)電器元件(jian)導(dao)致(zhi)所(suo)加的電壓分壓,造成(cheng)數據的誤差。
3、若端子排線路復雜,無法進行試驗,則可以直接把(ba)電(dian)(dian)壓,電(dian)(dian)流加在儀表上,應注意要(yao)脫開外電(dian)(dian)路,所加電(dian)(dian)壓線的觸頭應該保持一定間隙,防止短路。
4、若發現所測(ce)電壓,電流數(shu)據有微小(xiao)波動(dong)(dong)時(shi),因先檢查是(shi)否所加(jia)(jia)頻率(lv)是(shi)50Hz,然后先把電壓,電流加(jia)(jia)到滿量程,一般情況下可(ke)以消(xiao)除(chu)波動(dong)(dong)。
5、若發現所測的電壓,電流(liu),有(you)功,無功的值與(yu)標準(zhun)值有(you)明(ming)顯差異時,因先檢查是(shi)(shi)否(fou)(fou)是(shi)(shi)回路問題(ti),加錯(cuo)線(xian)或(huo)者相序弄等,然后在檢查是(shi)(shi)否(fou)(fou)是(shi)(shi)該(gai)表變比問題(ti),與(yu)之前所記錄的電壓互(hu)感器、電流(liu)互(hu)感器變比,進(jin)(jin)行比較。若設(she)(she)置錯(cuo)誤(wu),則對多功能電力儀表進(jin)(jin)行設(she)(she)置,設(she)(she)置正確后,在進(jin)(jin)行校驗。
6、若發現(xian)所測電流表,功率表是顯(xian)示負(fu)數,則要檢(jian)查是否是所加(jia)電流極性錯誤。