表(biao)(biao)有用(yong)于計量(liang)檢定用(yong)電量(liang)應用(yong)狀(zhuang)況(kuang)的(de)(de)無線水表(biao)(biao)，常統一安裝在電表(biao)(biao)箱內或金屬材料表(biao)(biao)柜內，用(yong)于連續的(de)(de)計量(liang)檢定客戶的(de)(de)耗電量(liang)狀(zhuang)況(kuang)。那(nei)麼，怎(zen)樣來(lai)挑選電表(biao)(biao)也變(bian)成(cheng)人們成(cheng)套設備生產(chan)廠(chang)家關鍵(jian)事宜之(zhi)一。依據很多年累積的(de)(de)工作經驗（experience)給大伙兒實際敘述(shu)一下電表(biao)(biao)的(de)(de)挑選。

一、電表的性能參數(parameter)

如(ru)今銷售市場上普遍電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)的(de)(de)性能(neng)參(can)數為(wei)：額(e)(e)定電(dian)(dian)(dian)(dian)(dian)流(liu)220V，級別為(wei)2.0級、頻率(frequency)為(wei)50HZ。不一(yi)樣的(de)(de)主要參(can)數是電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)的(de)(de)校準(zhun)電(dian)(dian)(dian)(dian)(dian)流(liu)(Electron flow)和額(e)(e)定值較(jiao)(jiao)大(da)電(dian)(dian)(dian)(dian)(dian)流(liu)。校準(zhun)電(dian)(dian)(dian)(dian)(dian)流(liu)就是指(zhi)電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)長期(qi)性一(yi)切(qie)正常運作的(de)(de)基礎電(dian)(dian)(dian)(dian)(dian)流(liu)，是明確電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)相關特點的(de)(de)電(dian)(dian)(dian)(dian)(dian)流(liu)值，以Ib表(biao)(biao)達。額(e)(e)定值較(jiao)(jiao)大(da)電(dian)(dian)(dian)(dian)(dian)流(liu)就是指(zhi)電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)能(neng)考慮其(qi)生產(chan)制造標(biao)準(zhun)的(de)(de)度的(de)(de)較(jiao)(jiao)大(da)電(dian)(dian)(dian)(dian)(dian)流(liu)值，以Imax表(biao)(biao)達。如(ru)Imax低(di)于基礎電(dian)(dian)(dian)(dian)(dian)流(liu)的(de)(de)1時，只標(biao)出基礎電(dian)(dian)(dian)(dian)(dian)流(liu)。因而(er)，采用哪些的(de)(de)電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)一(yi)定要依據(ju)負(fu)載電(dian)(dian)(dian)(dian)(dian)流(liu)的(de)(de)尺寸(cun)來明確。用電(dian)(dian)(dian)(dian)(dian)負(fu)荷的(de)(de)限(xian)制應不超(chao)出電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)的(de)(de)短(duan)路容(rong)量，低(di)限(xian)不可小(xiao)于電(dian)(dian)(dian)(dian)(dian)表(biao)(biao)容(rong)許(xu)偏(pian)差要求的(de)(de)負(fu)載電(dian)(dian)(dian)(dian)(dian)流(liu)值。

此外，家中常(chang)見的負載電(dian)流(Electron flow)是(shi)高于10%的校準(zhun)電(dian)流值(zhi)，那樣即能(neng)確保電(dian)表的計量檢(jian)定性(xing)，又能(neng)確保電(dian)表自身的安全性(xing)。

二、電表不應(ying)有潛動狀況

潛(qian)動就是(shi)指當(dang)電(dian)(dian)表(biao)(biao)(biao)(biao)再加(jia)額定電(dian)(dian)流，但負(fu)載(zai)電(dian)(dian)流(Electron flow)為零時(shi)，電(dian)(dian)表(biao)(biao)(biao)(biao)的(de)(de)輪(lun)盤不斷的(de)(de)持續（Continuity)旋轉(zhuan)。因(yin)(yin)而，當(dang)你要想評(ping)定(近義(yi)詞:判(pan)斷、分辨、裁定)一(yi)塊電(dian)(dian)表(biao)(biao)(biao)(biao)是(shi)不是(shi)有(you)潛(qian)動狀況，將(jiang)220V的(de)(de)交流電(dian)(dian)流加(jia)進(jin)電(dian)(dian)表(biao)(biao)(biao)(biao)的(de)(de)工作電(dian)(dian)壓磁圈(quan)(winding)兩邊（即(ji)電(dian)(dian)能表(biao)(biao)(biao)(biao)接線端鈕的(de)(de)1端和3端或5端），這時(shi)電(dian)(dian)表(biao)(biao)(biao)(biao)的(de)(de)電(dian)(dian)流磁圈(quan)因(yin)(yin)為無負(fu)載(zai)電(dian)(dian)流存有(you)，所欲電(dian)(dian)表(biao)(biao)(biao)(biao)的(de)(de)輪(lun)盤應終(zhong)止旋轉(zhuan)或數多旋轉(zhuan)不超出一(yi)一(yi)圈(quan)定位及格，不然為不過關。

三、電表的外型巡視(shi)

1.電表接線端鈕(niu)的表蓋上(shang)應有顯著的接線電路原理圖。

2.電表(biao)出廠銘牌(pai)上(shang)的筆跡（包含計度(du)器上(shang)的筆跡）要(yao)清楚，標識要(yao)詳細，表(biao)帶(dai)無(wu)毀壞，密封性好些。

3.電表應有供計讀轉速(su)的色(se)標(biao)或色(se)標(biao)部(bu)位(wei)（position )（當防潛(qian)動針距(ju)防潛(qian)鉤終時，色(se)標(biao)應在正前(qian)）。

4.電(dian)表的(de)輪盤(pan)在旋轉時應無蹭(ceng)盤(pan)狀(zhuang)況，另外(wai)表帶應有鉛(qian)(外(wai)型(xing):帶天(tian)藍色的(de)銀色)封。

5.為(wei)保證電表(biao)的品質，是采(cai)用經營規(gui)模很大(da)的生產(chan)制造(Produce)生產(chan)廠(chang)家(jia)，選購后一定要(yao)送至(zhi)本地(di)有(you)段計量檢定單(dan)位(wei)校檢及格后，方可應用。

四、電表的安裝與應(ying)用

電表(biao)(biao)需裝在(zai)易抄(chao)讀(du)表(biao)(biao)，光(guang)源充裕，干躁且不會受到震動的(de)地區，是距路面未17-2m的(de)地方(fang)，應該和別的(de)用(yong)電量機器設(she)備有一定的(de)間距，禁(jin)止在(zai)有浸蝕(shi)(釋意(yi):指(zhi)腐化(hua)、消退、腐蝕(shi)等)氣體的(de)地區安裝電表(biao)(biao)。另外，電表(biao)(biao)不必安裝在(zai)密(mi)封性(xing)的(de)小箱(xiang)子(zi)里，那樣電表(biao)(biao)不容易熱管(guan)散熱，易絕(jue)緣層(insulated)脆化(hua)。

電(dian)表(biao)耐受性自然環(huan)(huan)境(jing)標準的工作能(neng)力一般分成P（或不(bu)標識）、S、A、B四組。她(ta)們的參比(bi)溫度(du)（temperature)均(jun)為(wei) 23℃，參比(bi)環(huan)(huan)境(jing)濕度(du)均(jun)為(wei)40-60%。P、S的溫度(du)規定(ding)值均(jun)為(wei)-25~ 40℃環(huan)(huan)境(jing)濕度(du)均(jun)為(wei)25%~80%。A、B的溫度(du)規定(ding)值各自為(wei)0~ 40℃和(he)-20~ 50℃，環(huan)(huan)境(jing)濕度(du)均(jun)為(wei)25~80%。實(shi)際安裝哪(na)些的電(dian)表(biao)要(yao)依據本地的實(shi)際上(shang)自然環(huan)(huan)境(jing)標準定(ding)。

電(dian)表一定(ding)要依照路線(xian)圖(tu)恰當的(de)連(lian)接電(dian)力網，電(dian)表的(de)電(dian)流(liu)(Electron flow)磁(ci)圈(quan)(quan)(winding)應串接在開關電(dian)源的(de)相線(xian)（別名火線(xian)零線(xian)），工(gong)作(zuo)電(dian)壓磁(ci)圈(quan)(quan)則(ze)跨收到(dao)開關電(dian)源的(de)相線(xian)和零線(xian)中(zhong)間。避免因(yin)為不正確(que)接線(xian)導致電(dian)表損(sun)壞或不正確(que)計量(liang)檢定(ding)。一旦(dan)產生常見故障一定(ding)要請技術人(ren)員檢修(xiu)和校驗，不可以隨意開啟鉛(qian)(外(wai)型:帶天藍色的(de)銀色)封，私(si)自(zi)修(xiu)改路線(xian)及拆換元器件。

應用電表(biao)時，一定要將(jiang)電表(biao)接(jie)線(xian)端(duan)(duan)子的(de)螺釘(ding)（screw)扭緊(jin)，使輸電線(xian)與接(jie)線(xian)端(duan)(duan)子排密不(bu)可分觸碰(peng)，避免因為松脫導致(zhi)點火(huo)或觸碰(peng)不(bu)太好，使電表(biao)的(de)接(jie)線(xian)端(duan)(duan)子燒毀，使電表(biao)轉停，撥通量(liang)遺失。