WEIGEL電流表EQ144K/1A/20A 翊霈優質供應

WEIGEL電流表EQ144K/1A/20A 翊霈優質供應

檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)是(shi)(shi)(shi)(shi)(shi)磁電(dian)(dian)(dian)式儀表，它(ta)(ta)是(shi)(shi)(shi)(shi)(shi)根據載流(liu)(liu)(liu)線(xian)圈(quan)(quan)在(zai)磁場(chang)中(zhong)(zhong)(zhong)受到(dao)(dao)力矩(ju)(ju)而(er)(er)偏(pian)(pian)(pian)轉(zhuan)(zhuan)的(de)(de)(de)(de)原(yuan)理(li)制(zhi)成的(de)(de)(de)(de)。普通(tong)(tong)(tong)電(dian)(dian)(dian)表中(zhong)(zhong)(zhong)線(xian)圈(quan)(quan)是(shi)(shi)(shi)(shi)(shi)安放在(zai)軸承(cheng)上(shang)(shang)(shang)(shang)，用(yong)(yong)彈簧(huang)游絲來維持平(ping)衡，用(yong)(yong)指針(zhen)來指示偏(pian)(pian)(pian)轉(zhuan)(zhuan)。由(you)于(yu)(yu)軸承(cheng)有摩擦，被(bei)測電(dian)(dian)(dian)流(liu)(liu)(liu)不(bu)(bu)能(neng)太(tai)弱。檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)使(shi)(shi)用(yong)(yong)極細的(de)(de)(de)(de)金屬(shu)懸(xuan)(xuan)絲代替(ti)軸承(cheng)懸(xuan)(xuan)掛在(zai)磁場(chang)中(zhong)(zhong)(zhong)，由(you)于(yu)(yu)懸(xuan)(xuan)絲細而(er)(er)長(chang)(chang)，反抗力矩(ju)(ju)很小，所以(yi)(yi)(yi)有很弱的(de)(de)(de)(de)電(dian)(dian)(dian)流(liu)(liu)(liu)通(tong)(tong)(tong)過線(xian)圈(quan)(quan)就足(zu)以(yi)(yi)(yi)使(shi)(shi)它(ta)(ta)產(chan)生(sheng)顯(xian)著的(de)(de)(de)(de)偏(pian)(pian)(pian)轉(zhuan)(zhuan)。因而(er)(er)檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)比一般的(de)(de)(de)(de)電(dian)(dian)(dian)流(liu)(liu)(liu)表靈敏的(de)(de)(de)(de)多，可以(yi)(yi)(yi)測量微電(dian)(dian)(dian)流(liu)(liu)(liu)（10-7~10-10A）或者(zhe)微電(dian)(dian)(dian)壓(ya)（10-3~10-6V），如光電(dian)(dian)(dian)流(liu)(liu)(liu)、生(sheng)理(li)電(dian)(dian)(dian)流(liu)(liu)(liu)、溫差(cha)電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)(dong)(dong)勢等(deng)。*記錄神經動(dong)(dong)(dong)(dong)(dong)(dong)作(zuo)(zuo)電(dian)(dian)(dian)位(wei)(wei)，就是(shi)(shi)(shi)(shi)(shi)用(yong)(yong)此類(lei)儀器實(shi)現的(de)(de)(de)(de)。以(yi)(yi)(yi)光點式檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)為(wei)例，檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)由(you)三(san)部(bu)(bu)分(fen)組成：(1)磁場(chang)部(bu)(bu)分(fen)：由(you)永磁鐵(tie)(N,S)產(chan)生(sheng)磁場(chang)，圓柱形軟鐵(tie)心(J)使(shi)(shi)氣隙中(zhong)(zhong)(zhong)磁場(chang)呈(cheng)均勻輻射(she)(she)狀(zhuang)(zhuang)。(2)偏(pian)(pian)(pian)轉(zhuan)(zhuan)部(bu)(bu)分(fen)：能(neng)在(zai)氣隙中(zhong)(zhong)(zhong)轉(zhuan)(zhuan)動(dong)(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)(de)矩(ju)(ju)形線(xian)圈(quan)(quan)C及從上(shang)(shang)(shang)(shang)下拉緊線(xian)圈(quan)(quan)的(de)(de)(de)(de)金屬(shu)張絲E,只要有很小的(de)(de)(de)(de)力矩(ju)(ju)作(zuo)(zuo)用(yong)(yong)，就能(neng)使(shi)(shi)線(xian)圈(quan)(quan)偏(pian)(pian)(pian)轉(zhuan)(zhuan)。(3)讀數部(bu)(bu)分(fen)：小鏡(jing)M固定(ding)在(zai)動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)上(shang)(shang)(shang)(shang)，它(ta)(ta)把(ba)光源射(she)(she)進來的(de)(de)(de)(de)光束(shu)反射(she)(she)到(dao)(dao)標尺上(shang)(shang)(shang)(shang)形成一個光標，當電(dian)(dian)(dian)流(liu)(liu)(liu)流(liu)(liu)(liu)過動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)時，動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)受力偏(pian)(pian)(pian)轉(zhuan)(zhuan)而(er)(er)帶動(dong)(dong)(dong)(dong)(dong)(dong)小鏡(jing)M轉(zhuan)(zhuan)過?角，因而(er)(er)反射(she)(she)光束(shu)偏(pian)(pian)(pian)轉(zhuan)(zhuan)的(de)(de)(de)(de)角度為(wei),光標在(zai)標尺上(shang)(shang)(shang)(shang)移動(dong)(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)(de)距離(li)n=L*α，L為(wei)小鏡(jing)到(dao)(dao)標尺的(de)(de)(de)(de)距離(li)，實(shi)際上(shang)(shang)(shang)(shang)阻(zu)(zu)尼(ni)(ni)(ni)總是(shi)(shi)(shi)(shi)(shi)存在(zai)的(de)(de)(de)(de),當R≠∞,D≠0時有三(san)種運(yun)動(dong)(dong)(dong)(dong)(dong)(dong)狀(zhuang)(zhuang)態(tai)(tai).1)欠阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)(zhuang)態(tai)(tai):此時外(wai)電(dian)(dian)(dian)阻(zu)(zu)R較(jiao)大，β<ω,動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)以(yi)(yi)(yi)平(ping)衡位(wei)(wei)置為(wei)中(zhong)(zhong)(zhong)心作(zuo)(zuo)衰減振(zhen)(zhen)動(dong)(dong)(dong)(dong)(dong)(dong)，并且逐漸趨(qu)緊于(yu)(yu)平(ping)衡位(wei)(wei)置。2)臨(lin)界阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)(zhuang)態(tai)(tai):R=Rc,β=ω,動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)無振(zhen)(zhen)動(dong)(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)(de)很快達到(dao)(dao)平(ping)衡位(wei)(wei)置，此時的(de)(de)(de)(de)外(wai)電(dian)(dian)(dian)阻(zu)(zu)稱為(wei)臨(lin)界電(dian)(dian)(dian)阻(zu)(zu)Rc，一般來說，檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)臨(lin)界阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)(zhuang)態(tai)(tai)是(shi)(shi)(shi)(shi)(shi)它(ta)(ta)的(de)(de)(de)(de)理(li)想工作(zuo)(zuo)狀(zhuang)(zhuang)態(tai)(tai)。3)過阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)(zhuang)態(tai)(tai):當β>ω,即R<Rc,此時動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)也是(shi)(shi)(shi)(shi)(shi)做(zuo)單向偏(pian)(pian)(pian)轉(zhuan)(zhuan)運(yun)動(dong)(dong)(dong)(dong)(dong)(dong)，緩慢的(de)(de)(de)(de)趨(qu)向平(ping)衡位(wei)(wei)置。R越(yue)小，到(dao)(dao)達平(ping)衡位(wei)(wei)置的(de)(de)(de)(de)時間(jian)越(yue)長(chang)(chang)。因為(wei)過阻(zu)(zu)尼(ni)(ni)(ni)運(yun)動(dong)(dong)(dong)(dong)(dong)(dong)中(zhong)(zhong)(zhong)，動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)到(dao)(dao)達平(ping)衡的(de)(de)(de)(de)時間(jian)長(chang)(chang)，而(er)(er)且不(bu)(bu)易判斷(duan)動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)是(shi)(shi)(shi)(shi)(shi)否(fou)到(dao)(dao)達平(ping)衡位(wei)(wei)置，因此它(ta)(ta)對于(yu)(yu)測量是(shi)(shi)(shi)(shi)(shi)不(bu)(bu)利(li)的(de)(de)(de)(de)。由(you)于(yu)(yu)檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)很靈敏，一般通(tong)(tong)(tong)過電(dian)(dian)(dian)流(liu)(liu)(liu)不(bu)(bu)能(neng)超過1μA。電(dian)(dian)(dian)壓(ya)經過兩次分(fen)壓(ya)后(hou)得到(dao)(dao)很小的(de)(de)(de)(de)電(dian)(dian)(dian)壓(ya)(常(chang)小于(yu)(yu)1mV)后(hou)才加(jia)到(dao)(dao)檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)電(dian)(dian)(dian)路中(zhong)(zhong)(zhong)。第(di)一次采(cai)用(yong)(yong)滑線(xian)變阻(zu)(zu)器分(fen)壓(ya)，第(di)二次采(cai)用(yong)(yong)固定(ding)電(dian)(dian)(dian)阻(zu)(zu)R1/R0?≈10-3~10-4的(de)(de)(de)(de)數量級分(fen)壓(ya)。K2是(shi)(shi)(shi)(shi)(shi)換向開關，用(yong)(yong)它(ta)(ta)可以(yi)(yi)(yi)變換過檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)電(dian)(dian)(dian)流(liu)(liu)(liu)方向， K3是(shi)(shi)(shi)(shi)(shi)阻(zu)(zu)尼(ni)(ni)(ni)開關，將它(ta)(ta)合(he)上(shang)(shang)(shang)(shang)就可以(yi)(yi)(yi)將檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)短路，檢(jian)(jian)(jian)流(liu)(liu)(liu)計(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)動(dong)(dong)(dong)(dong)(dong)(dong)圈(quan)(quan)就停(ting)止振(zhen)(zhen)動(dong)(dong)(dong)(dong)(dong)(dong)。
其結構(圖(tu)1) 和工作(zuo)(zuo)原理與磁電(dian)(dian)(dian)系(xi)電(dian)(dian)(dian)表基本相同。作(zuo)(zuo)為檢(jian)流(liu)(liu)計(ji)(ji)(ji)，要求有較(jiao)高(gao)的(de)靈(ling)敏(min)度，主要是(shi)電(dian)(dian)(dian)壓靈(ling)敏(min)度和電(dian)(dian)(dian)流(liu)(liu)靈(ling)敏(min)度。為提高(gao)電(dian)(dian)(dian)流(liu)(liu)靈(ling)敏(min)度，通常要增加(jia)轉動(dong)(dong)力(li)矩(ju)(ju)，例如加(jia)強磁場和增加(jia)動(dong)(dong)圈匝(za)數。但限于(yu)氣(qi)隙尺(chi)寸，須(xu)用(yong)(yong)(yong)很(hen)細的(de)導(dao)線繞制動(dong)(dong)圈。因(yin)此(ci)電(dian)(dian)(dian)流(liu)(liu)靈(ling)敏(min)度高(gao)的(de)檢(jian)流(liu)(liu)計(ji)(ji)(ji)的(de)動(dong)(dong)圈電(dian)(dian)(dian)阻(內阻)較(jiao)高(gao)。此(ci)外(wai)，要降(jiang)低反抗力(li)矩(ju)(ju)，可(ke)采用(yong)(yong)(yong)力(li)矩(ju)(ju)很(hen)弱的(de)拉絲（或懸(xuan)絲）將(jiang)動(dong)(dong)圈安置在(zai)(zai)永磁鐵的(de)氣(qi)隙中(zhong)。為此(ci)，檢(jian)流(liu)(liu)計(ji)(ji)(ji)使用(yong)(yong)(yong)時(shi)要保持水平位置。檢(jian)流(liu)(liu)計(ji)(ji)(ji)動(dong)(dong)圈沒有金屬框架，阻尼(ni)力(li)矩(ju)(ju)由動(dong)(dong)圈本身提供(gong),動(dong)(dong)圈在(zai)(zai)氣(qi)隙磁場中(zhong)運動(dong)(dong)時(shi),切割磁通而產(chan)生電(dian)(dian)(dian)動(dong)(dong)勢，此(ci)電(dian)(dian)(dian)動(dong)(dong)勢引起(qi)的(de)流(liu)(liu)過動(dong)(dong)圈和外(wai)電(dian)(dian)(dian)路的(de)電(dian)(dian)(dian)流(liu)(liu)，在(zai)(zai)檢(jian)流(liu)(liu)計(ji)(ji)(ji)中(zhong)又(you)與磁場作(zuo)(zuo)用(yong)(yong)(yong)產(chan)生阻尼(ni)力(li)矩(ju)(ju)。因(yin)此(ci)，外(wai)電(dian)(dian)(dian)路的(de)結構要影響檢(jian)流(liu)(liu)計(ji)(ji)(ji)阻尼(ni)的(de)強弱。若(ruo)使檢(jian)流(liu)(liu)計(ji)(ji)(ji)指示(shi)迅速達(da)到穩定，應令其工作(zuo)(zuo)在(zai)(zai)稍欠(qian)阻尼(ni)狀態。磁電(dian)(dian)(dian)系(xi)檢(jian)流(liu)(liu)計(ji)(ji)(ji)是(shi)很(hen)精細的(de)電(dian)(dian)(dian)表，不(bu)使用(yong)(yong)(yong)時(shi)，須(xu)將(jiang)兩端(duan)短路，這時(shi)阻尼(ni)強，可(ke)保護檢(jian)流(liu)(liu)計(ji)(ji)(ji)可(ke)動(dong)(dong)部分少受損(sun)害。
檢(jian)流(liu)計刻(ke)度(du)盤上的刻(ke)度(du)分格(ge)是(shi)均勻的，零點(dian)標(biao)在度(du)盤中心。動圈(quan)左右偏轉，都可(ke)讀數(shu)(shu)。刻(ke)度(du)上雖然(ran)標(biao)有數(shu)(shu)值，只是(shi)表(biao)示分格(ge)數(shu)(shu)；用(yong)于測電(dian)流(liu)、電(dian)壓(ya)時，要另行(xing)標(biao)定刻(ke)度(du)分格(ge)所代表(biao)的準確數(shu)(shu)值。
磁電(dian)(dian)(dian)系檢(jian)(jian)流計的(de)(de)電(dian)(dian)(dian)流靈(ling)敏(min)(min)度(du)以電(dian)(dian)(dian)流常(chang)數(shu)（電(dian)(dian)(dian)流靈(ling)敏(min)(min)度(du)與電(dian)(dian)(dian)流常(chang)數(shu)互為倒數(shu)）表示(shi)，可達10-9安/分格(ge)或更高(gao)，內(nei)(nei)阻(zu)達幾千歐(ou)。用(yong)檢(jian)(jian)流計測微弱電(dian)(dian)(dian)壓(ya)時，要求有較高(gao)的(de)(de)電(dian)(dian)(dian)壓(ya)靈(ling)敏(min)(min)度(du)。因(yin)檢(jian)(jian)流計測量的(de)(de)基本量是(shi)電(dian)(dian)(dian)流，如(ru)要求在一定的(de)(de)被測電(dian)(dian)(dian)壓(ya)下(xia)能有較大(da)的(de)(de)電(dian)(dian)(dian)流通過檢(jian)(jian)流計，則希望(wang)檢(jian)(jian)流計有較低內(nei)(nei)阻(zu)，但此時電(dian)(dian)(dian)流的(de)(de)靈(ling)敏(min)(min)度(du)降低。因(yin)此，電(dian)(dian)(dian)壓(ya)靈(ling)敏(min)(min)度(du)高(gao)的(de)(de)檢(jian)(jian)流計,其電(dian)(dian)(dian)流靈(ling)敏(min)(min)度(du)要低些（例如(ru)10-7安/分格(ge)）。
為(wei)使(shi)用方(fang)便(bian)，可(ke)將磁電系(xi)檢(jian)流計做成(cheng)便(bian)攜式，動圈用張絲(si)拉緊，并采用光線多次反射(she)以(yi)提高靈敏(min)度。
光(guang)電放大式(shi)檢流(liu)(liu)(liu)計(ji) 　將(jiang)光(guang)電放大器與兩個磁電系檢流(liu)(liu)(liu)計(ji)結合在一起即構(gou)成圖2所示的光(guang)電放大式(shi)檢流(liu)(liu)(liu)計(ji)。初級檢流(liu)(liu)(liu)計(ji)接在被測回路中，它的小鏡將(jiang)光(guang)線反射(she)到差(cha)分(fen)光(guang)電池上。兩光(guang)電池的輸(shu)出電流(liu)(liu)(liu)之差(cha)流(liu)(liu)(liu)入次級檢流(liu)(liu)(liu)計(ji)G2。如此(ci)可(ke)獲得較(jiao)強的信號。為使(shi)檢流(liu)(liu)(liu)計(ji)工作(zuo)穩定，通常采用負反饋線路。
測(ce)短(duan)暫(zan)脈(mo)沖(chong)(chong)電(dian)(dian)(dian)流(liu)(liu)(liu)所含電(dian)(dian)(dian)荷(he)(he)量(liang)(liang)(liang)(liang)(liang)(liang)的(de)(de)(de)磁(ci)電(dian)(dian)(dian)系檢(jian)流(liu)(liu)(liu)計(ji)。其(qi)可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分具有(you)較大(da)慣量(liang)(liang)(liang)(liang)(liang)(liang)。為(wei)保證測(ce)量(liang)(liang)(liang)(liang)(liang)(liang)準確(que)度，理(li)論(lun)(lun)上(shang)要求在(zai)短(duan)暫(zan)脈(mo)沖(chong)(chong)電(dian)(dian)(dian)流(liu)(liu)(liu)通(tong)過(guo)檢(jian)流(liu)(liu)(liu)計(ji)時，可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分應靜止不動(dong)(dong)(dong)(dong)(dong)；短(duan)暫(zan)脈(mo)沖(chong)(chong)消失后，可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分或單(dan)方(fang)向，或以(yi)刻度零點為(wei)中心作衰減擺(bai)動(dong)(dong)(dong)(dong)(dong)。不論(lun)(lun)哪種情況，取(qu)大(da)偏轉或擺(bai)動(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)第(di)一次大(da)值αm來表示電(dian)(dian)(dian)荷(he)(he)量(liang)(liang)(liang)(liang)(liang)(liang)Q的(de)(de)(de)大(da)小(xiao)，即αm=S,Sq是沖(chong)(chong)擊檢(jian)流(liu)(liu)(liu)計(ji)的(de)(de)(de)沖(chong)(chong)擊靈敏度。可(ke)(ke)通(tong)過(guo)接入光電(dian)(dian)(dian)放大(da)器來提(ti)高沖(chong)(chong)擊檢(jian)流(liu)(liu)(liu)計(ji)的(de)(de)(de)Sq。普通(tong)磁(ci)電(dian)(dian)(dian)系檢(jian)流(liu)(liu)(liu)計(ji)也可(ke)(ke)用以(yi)測(ce)電(dian)(dian)(dian)荷(he)(he)量(liang)(liang)(liang)(liang)(liang)(liang)，但其(qi)可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分的(de)(de)(de)慣量(liang)(liang)(liang)(liang)(liang)(liang)不夠大(da)，會產(chan)生測(ce)量(liang)(liang)(liang)(liang)(liang)(liang)誤差。一種動(dong)(dong)(dong)(dong)(dong)磁(ci)鐵(tie)式檢(jian)流(liu)(liu)(liu)計(ji)。可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分由小(xiao)塊永磁(ci)鐵(tie)和小(xiao)鏡構成(cheng)，其(qi)上(shang)下被張絲拉(la)緊。小(xiao)磁(ci)鐵(tie)處于(yu)用疊(die)片(pian)組成(cheng)的(de)(de)(de)磁(ci)極(ji)(ji)間，磁(ci)極(ji)(ji)上(shang)繞(rao)有(you)線(xian)圈，被檢(jian)測(ce)電(dian)(dian)(dian)流(liu)(liu)(liu)i通(tong)入此線(xian)圈后,由于(yu)可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分的(de)(de)(de)質量(liang)(liang)(liang)(liang)(liang)(liang)和慣性都(dou)較小(xiao)，因此,可(ke)(ke)動(dong)(dong)(dong)(dong)(dong)部(bu)分可(ke)(ke)跟隨電(dian)(dian)(dian)流(liu)(liu)(liu)i引起的(de)(de)(de)交(jiao)變(bian)磁(ci)場(chang)的(de)(de)(de)瞬時值的(de)(de)(de)變(bian)化動(dong)(dong)(dong)(dong)(dong)作。小(xiao)鏡左右擺(bai)動(dong)(dong)(dong)(dong)(dong)，光線(xian)被小(xiao)鏡反射后,在(zai)標(biao)尺上(shang)形成(cheng)光帶(dai)。i為(wei)零時,小(xiao)鏡不動(dong)(dong)(dong)(dong)(dong),光帶(dai)縮(suo)成(cheng)一條線(xian)。??為使(shi)振動(dong)檢流計的靈敏度達(da)到高(gao)點，其(qi)可動(dong)部分(fen)的機械(xie)振動頻率應與外(wai)加電流頻率產(chan)生諧振。為(wei)此設置了另一(yi)套為(wei)調諧用的(de)永磁系統，它包(bao)括磁軛和一(yi)可旋動的(de)永磁鐵。旋(xuan)動(dong)(dong)永磁鐵可(ke)改變(bian)調諧系統磁軛的(de)(de)磁*度，即(ji)可(ke)改變(bian)與可(ke)動(dong)(dong)部分(fen)小磁鐵間(jian)的(de)(de)吸力(li)。這等效于調整(zheng)了可(ke)動(dong)(dong)部分(fen)中張絲的(de)(de)拉(la)力(li)，因此改變(bian)了可(ke)動(dong)(dong)部分(fen)的(de)(de)機械諧振頻率。這種(zhong)檢流計(ji)主要(yao)用于工頻，作指零儀表。
????WEIGEL安培表PQ72K 0-20MA

WEIGEL備件A1U2.2 13 4 0.5 H1
WEIGEL電流表0-50mA電流表 50VCATIII
WEIGEL備件674.110.00 EQ48K Sonder-MB: 0-250/500 mA Skala: 0-250/500 mA
WEIGEL備(bei)件DGW2.0
WEIGEL舵(duo)機計時(shi)器TYPE:BG40.×7/3121×0 SERIAL NO.:10T50 0508
WEIGEL分流器0.5 250A 60mV Q
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WEIGEL表(biao)100V
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WEIGEL電(dian)流顯示表PQ96K60-0-60mV DC本(ben)體型(xing)規:PQ96K
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WEIGELmeter with movingLSP48-4-20MA DC current
WEIGEL分流器1000A/60MV
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WEIGEL電壓表EQ96K-500V
WEIGEL電流(liu)表EQ48 150/5A
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WEIGEL電流表(biao)EQ96K 300/1
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WEIGEL備件(jian)AU2.0 Input: 0...5A Output: 0...20mA
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WEIGEL備件652.02.121600 SUS-01-Q R/G 220V DC
WEIGEL分(fen)流器869.7330.1 50KA/250ms
WEIGEL電(dian)流(liu)表EQ96-X 3000/1A
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WEIGEL電流表(biao)EQ 72E
WEIGEL分流器(qi)SHUNT 18000A/200MV/CLASS 0.5
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WEIGEL豎(shu)(shu)式(shi)指(zhi)針表MP48X24K 4~20mA 24mm×48mm豎(shu)(shu)式(shi)指(zhi)針表
WEIGEL電(dian)流(liu)表RW96MIN/MAX 0-1A 230V AC
WEIGEL備件EQ72K 100/5A 600V
WEIGEL電器件SHUNT 1500A/60MV/CLASS 0.5
WEIGEL電流表PQ72K 0-10V
WEIGEL橫(heng)式(shi)指針表(biao)MP48X96K(4~20mA 帶零位調(diao)整(zheng)）96mm×48mm橫(heng)式(shi)指針表(biao)
WEIGEL表DA12-NA40/F10R 72*24
WEIGEL備件EQ48-MESSB:10A-SKALA:0-10A+STTX*
WEIGEL電(dian)壓表(biao)PQ96K 0-10V 0-120% POTI (0-10VDC/1mA + scale 0-120% w.pot )
WEIGEL備件EQ72K 50/5A 600V
WEIGEL電流表PQ96K 0-6000A
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WEIGEL分(fen)流(liu)器KL0.5 2000Amp/150mV
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WEIGEL電流(liu)表PQ72K 0-100A 4-20MA
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WEIGEL電壓表EQ72K 0~750V
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WEIGEL分(fen)流(liu)器額(e)定電流(liu)50A 直流(liu)輸(shu)出要60mV 可以(yi)短時耐受(shou)5倍的(de)過流(liu)
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WEIGEL電流表PQ96K 10V 0-8000
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WEIGEL表UH230V 48-62HZ max.1.2VA
WEIGEL分流器(qi)安裝盤SHUNTISO. PLATE LARGE 155X90X6MM TRAFO，870-93260
WEIGEL表150v
WEIGEL電流(liu)表EQ96-X 100/1 0-100A/500A
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WEIGEL顯示器DAS10-40PIR S-Nr.943614008
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WEIGEL動鐵式儀表AC 0..600A （Moving-iron meter AC 0..600 A ）
WEIGEL備(bei)件LSP48CA
檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)是(shi)(shi)(shi)(shi)磁(ci)(ci)(ci)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)式儀(yi)表(biao)，它(ta)是(shi)(shi)(shi)(shi)根(gen)據載流(liu)(liu)(liu)(liu)(liu)(liu)線(xian)圈(quan)(quan)(quan)(quan)(quan)在(zai)(zai)磁(ci)(ci)(ci)場中(zhong)(zhong)受到(dao)(dao)力矩(ju)而(er)(er)偏(pian)(pian)轉(zhuan)(zhuan)的(de)(de)(de)原理(li)(li)制成的(de)(de)(de)。普通電(dian)(dian)(dian)(dian)(dian)(dian)(dian)表(biao)中(zhong)(zhong)線(xian)圈(quan)(quan)(quan)(quan)(quan)是(shi)(shi)(shi)(shi)安放(fang)在(zai)(zai)軸(zhou)承(cheng)(cheng)上，用(yong)(yong)彈簧游絲來維持平(ping)衡(heng)(heng)(heng)，用(yong)(yong)指針來指示偏(pian)(pian)轉(zhuan)(zhuan)。由(you)(you)于(yu)(yu)軸(zhou)承(cheng)(cheng)有(you)摩擦(ca)，被測電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)不能太(tai)弱。檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)使用(yong)(yong)極(ji)細的(de)(de)(de)金屬(shu)懸(xuan)絲代替(ti)軸(zhou)承(cheng)(cheng)懸(xuan)掛在(zai)(zai)磁(ci)(ci)(ci)場中(zhong)(zhong)，由(you)(you)于(yu)(yu)懸(xuan)絲細而(er)(er)長(chang)，反抗力矩(ju)很(hen)小(xiao)(xiao)(xiao)，所(suo)以(yi)(yi)有(you)很(hen)弱的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)通過(guo)(guo)(guo)線(xian)圈(quan)(quan)(quan)(quan)(quan)就(jiu)足以(yi)(yi)使它(ta)產生顯著(zhu)的(de)(de)(de)偏(pian)(pian)轉(zhuan)(zhuan)。因(yin)而(er)(er)檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)比一般的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)表(biao)靈(ling)敏的(de)(de)(de)多，可以(yi)(yi)測量(liang)微(wei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)（10-7~10-10A）或者微(wei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)（10-3~10-6V），如光電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)、生理(li)(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)、溫差電(dian)(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)(dong)勢等。*記錄神經動(dong)(dong)(dong)作電(dian)(dian)(dian)(dian)(dian)(dian)(dian)位(wei)，就(jiu)是(shi)(shi)(shi)(shi)用(yong)(yong)此(ci)類(lei)儀(yi)器實現(xian)的(de)(de)(de)。以(yi)(yi)光點式檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)為(wei)例，檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)由(you)(you)三部(bu)分組成：(1)磁(ci)(ci)(ci)場部(bu)分：由(you)(you)永(yong)磁(ci)(ci)(ci)鐵(N,S)產生磁(ci)(ci)(ci)場，圓柱形軟鐵心(J)使氣隙(xi)中(zhong)(zhong)磁(ci)(ci)(ci)場呈均勻輻射(she)狀(zhuang)。(2)偏(pian)(pian)轉(zhuan)(zhuan)部(bu)分：能在(zai)(zai)氣隙(xi)中(zhong)(zhong)轉(zhuan)(zhuan)動(dong)(dong)(dong)的(de)(de)(de)矩(ju)形線(xian)圈(quan)(quan)(quan)(quan)(quan)C及從(cong)上下拉(la)緊(jin)線(xian)圈(quan)(quan)(quan)(quan)(quan)的(de)(de)(de)金屬(shu)張絲E,只要(yao)有(you)很(hen)小(xiao)(xiao)(xiao)的(de)(de)(de)力矩(ju)作用(yong)(yong)，就(jiu)能使線(xian)圈(quan)(quan)(quan)(quan)(quan)偏(pian)(pian)轉(zhuan)(zhuan)。(3)讀數部(bu)分：小(xiao)(xiao)(xiao)鏡M固定在(zai)(zai)動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)上，它(ta)把光源射(she)進(jin)來的(de)(de)(de)光束反射(she)到(dao)(dao)標尺(chi)(chi)上形成一個光標，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)流(liu)(liu)(liu)(liu)(liu)(liu)過(guo)(guo)(guo)動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)時(shi)(shi)，動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)受力偏(pian)(pian)轉(zhuan)(zhuan)而(er)(er)帶(dai)動(dong)(dong)(dong)小(xiao)(xiao)(xiao)鏡M轉(zhuan)(zhuan)過(guo)(guo)(guo)?角(jiao)，因(yin)而(er)(er)反射(she)光束偏(pian)(pian)轉(zhuan)(zhuan)的(de)(de)(de)角(jiao)度為(wei),光標在(zai)(zai)標尺(chi)(chi)上移動(dong)(dong)(dong)的(de)(de)(de)距(ju)離n=L*α，L為(wei)小(xiao)(xiao)(xiao)鏡到(dao)(dao)標尺(chi)(chi)的(de)(de)(de)距(ju)離，實際(ji)上阻(zu)(zu)尼(ni)(ni)(ni)總(zong)是(shi)(shi)(shi)(shi)存在(zai)(zai)的(de)(de)(de),當(dang)R≠∞,D≠0時(shi)(shi)有(you)三種運動(dong)(dong)(dong)狀(zhuang)態(tai)(tai).1)欠阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)態(tai)(tai):此(ci)時(shi)(shi)外電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)R較大，β<ω,動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)以(yi)(yi)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)為(wei)中(zhong)(zhong)心作衰減(jian)振動(dong)(dong)(dong)，并且逐漸(jian)趨(qu)緊(jin)于(yu)(yu)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)。2)臨界(jie)阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)態(tai)(tai):R=Rc,β=ω,動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)無振動(dong)(dong)(dong)的(de)(de)(de)很(hen)快(kuai)達(da)到(dao)(dao)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)，此(ci)時(shi)(shi)的(de)(de)(de)外電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)稱為(wei)臨界(jie)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)Rc，一般來說，檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)的(de)(de)(de)臨界(jie)阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)態(tai)(tai)是(shi)(shi)(shi)(shi)它(ta)的(de)(de)(de)理(li)(li)想工作狀(zhuang)態(tai)(tai)。3)過(guo)(guo)(guo)阻(zu)(zu)尼(ni)(ni)(ni)狀(zhuang)態(tai)(tai):當(dang)β>ω,即R<Rc,此(ci)時(shi)(shi)動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)也(ye)是(shi)(shi)(shi)(shi)做單向(xiang)偏(pian)(pian)轉(zhuan)(zhuan)運動(dong)(dong)(dong)，緩慢的(de)(de)(de)趨(qu)向(xiang)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)。R越(yue)小(xiao)(xiao)(xiao)，到(dao)(dao)達(da)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)的(de)(de)(de)時(shi)(shi)間(jian)(jian)越(yue)長(chang)。因(yin)為(wei)過(guo)(guo)(guo)阻(zu)(zu)尼(ni)(ni)(ni)運動(dong)(dong)(dong)中(zhong)(zhong)，動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)到(dao)(dao)達(da)平(ping)衡(heng)(heng)(heng)的(de)(de)(de)時(shi)(shi)間(jian)(jian)長(chang)，而(er)(er)且不易判斷動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)是(shi)(shi)(shi)(shi)否到(dao)(dao)達(da)平(ping)衡(heng)(heng)(heng)位(wei)置(zhi)，因(yin)此(ci)它(ta)對于(yu)(yu)測量(liang)是(shi)(shi)(shi)(shi)不利的(de)(de)(de)。由(you)(you)于(yu)(yu)檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)很(hen)靈(ling)敏，一般通過(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)不能超過(guo)(guo)(guo)1μA。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)經過(guo)(guo)(guo)兩(liang)次(ci)(ci)分壓(ya)(ya)后得到(dao)(dao)很(hen)小(xiao)(xiao)(xiao)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(常小(xiao)(xiao)(xiao)于(yu)(yu)1mV)后才加到(dao)(dao)檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路中(zhong)(zhong)。第(di)一次(ci)(ci)采(cai)用(yong)(yong)滑(hua)線(xian)變阻(zu)(zu)器分壓(ya)(ya)，第(di)二(er)次(ci)(ci)采(cai)用(yong)(yong)固定電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)R1/R0?≈10-3~10-4的(de)(de)(de)數量(liang)級分壓(ya)(ya)。K2是(shi)(shi)(shi)(shi)換向(xiang)開(kai)關(guan)(guan)，用(yong)(yong)它(ta)可以(yi)(yi)變換過(guo)(guo)(guo)檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)方(fang)向(xiang)， K3是(shi)(shi)(shi)(shi)阻(zu)(zu)尼(ni)(ni)(ni)開(kai)關(guan)(guan)，將(jiang)(jiang)它(ta)合上就(jiu)可以(yi)(yi)將(jiang)(jiang)檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)短路，檢(jian)流(liu)(liu)(liu)(liu)(liu)(liu)計(ji)的(de)(de)(de)動(dong)(dong)(dong)圈(quan)(quan)(quan)(quan)(quan)就(jiu)停止振動(dong)(dong)(dong)。
其(qi)結構(gou)(圖1) 和(he)工(gong)作(zuo)原理與磁電(dian)系電(dian)表基本(ben)相同。作(zuo)為(wei)檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)，要(yao)(yao)(yao)求有較高的(de)靈(ling)(ling)敏(min)(min)度，主(zhu)要(yao)(yao)(yao)是電(dian)壓靈(ling)(ling)敏(min)(min)度和(he)電(dian)流(liu)(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度。為(wei)提高電(dian)流(liu)(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度，通常要(yao)(yao)(yao)增加(jia)(jia)轉動(dong)力(li)(li)(li)矩，例(li)如(ru)加(jia)(jia)強磁場(chang)和(he)增加(jia)(jia)動(dong)圈(quan)(quan)(quan)匝(za)數。但限于氣(qi)隙尺寸，須(xu)用(yong)(yong)(yong)很(hen)細的(de)導(dao)線繞制(zhi)動(dong)圈(quan)(quan)(quan)。因(yin)此電(dian)流(liu)(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度高的(de)檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)的(de)動(dong)圈(quan)(quan)(quan)電(dian)阻(zu)(內阻(zu))較高。此外，要(yao)(yao)(yao)降低(di)反抗力(li)(li)(li)矩，可(ke)(ke)采(cai)用(yong)(yong)(yong)力(li)(li)(li)矩很(hen)弱(ruo)的(de)拉絲（或懸(xuan)絲）將動(dong)圈(quan)(quan)(quan)安置在永磁鐵的(de)氣(qi)隙中。為(wei)此，檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)使用(yong)(yong)(yong)時(shi)要(yao)(yao)(yao)保持水平位置。檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)動(dong)圈(quan)(quan)(quan)沒有金屬框架(jia)，阻(zu)尼力(li)(li)(li)矩由動(dong)圈(quan)(quan)(quan)本(ben)身提供,動(dong)圈(quan)(quan)(quan)在氣(qi)隙磁場(chang)中運動(dong)時(shi),切割磁通而(er)產生電(dian)動(dong)勢，此電(dian)動(dong)勢引起的(de)流(liu)(liu)(liu)(liu)過動(dong)圈(quan)(quan)(quan)和(he)外電(dian)路(lu)的(de)電(dian)流(liu)(liu)(liu)(liu)，在檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)中又與磁場(chang)作(zuo)用(yong)(yong)(yong)產生阻(zu)尼力(li)(li)(li)矩。因(yin)此，外電(dian)路(lu)的(de)結構(gou)要(yao)(yao)(yao)影響(xiang)檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)阻(zu)尼的(de)強弱(ruo)。若使檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)指示迅速達(da)到穩定，應(ying)令其(qi)工(gong)作(zuo)在稍欠阻(zu)尼狀態。磁電(dian)系檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)是很(hen)精細的(de)電(dian)表，不使用(yong)(yong)(yong)時(shi)，須(xu)將兩端短路(lu)，這時(shi)阻(zu)尼強，可(ke)(ke)保護檢(jian)(jian)(jian)流(liu)(liu)(liu)(liu)計(ji)(ji)可(ke)(ke)動(dong)部分少(shao)受損害。
檢流(liu)(liu)計(ji)刻(ke)度(du)盤上(shang)的刻(ke)度(du)分(fen)格(ge)(ge)是均勻的，零點(dian)標在度(du)盤中心。動圈左右偏(pian)轉，都(dou)可讀數。刻(ke)度(du)上(shang)雖(sui)然標有數值，只是表(biao)示分(fen)格(ge)(ge)數；用于測電流(liu)(liu)、電壓時，要另行(xing)標定(ding)刻(ke)度(du)分(fen)格(ge)(ge)所代表(biao)的準確數值。
磁電(dian)(dian)(dian)(dian)(dian)系檢流(liu)(liu)(liu)計(ji)的(de)(de)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度以電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)常數(shu)（電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度與電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)常數(shu)互(hu)為倒數(shu)）表示，可達10-9安(an)/分格或更(geng)高，內阻達幾千(qian)歐。用(yong)檢流(liu)(liu)(liu)計(ji)測(ce)微弱電(dian)(dian)(dian)(dian)(dian)壓時，要求有(you)較(jiao)(jiao)高的(de)(de)電(dian)(dian)(dian)(dian)(dian)壓靈(ling)(ling)敏(min)(min)度。因檢流(liu)(liu)(liu)計(ji)測(ce)量的(de)(de)基本(ben)量是電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)，如(ru)要求在一定的(de)(de)被測(ce)電(dian)(dian)(dian)(dian)(dian)壓下能(neng)有(you)較(jiao)(jiao)大的(de)(de)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)通過檢流(liu)(liu)(liu)計(ji)，則希望(wang)檢流(liu)(liu)(liu)計(ji)有(you)較(jiao)(jiao)低內阻，但此(ci)時電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)靈(ling)(ling)敏(min)(min)度降低。因此(ci)，電(dian)(dian)(dian)(dian)(dian)壓靈(ling)(ling)敏(min)(min)度高的(de)(de)檢流(liu)(liu)(liu)計(ji),其電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)靈(ling)(ling)敏(min)(min)度要低些（例如(ru)10-7安(an)/分格）。
為使用(yong)方便(bian)，可將磁電系檢(jian)流計做(zuo)成便(bian)攜式，動圈用(yong)張絲拉(la)緊，并(bing)采(cai)用(yong)光(guang)線多(duo)次反射(she)以提高(gao)靈敏度。
光電(dian)放(fang)大(da)式檢(jian)(jian)流(liu)計(ji) 　將(jiang)光電(dian)放(fang)大(da)器(qi)與兩(liang)個磁電(dian)系檢(jian)(jian)流(liu)計(ji)結(jie)合在一起即構成圖2所示的(de)(de)光電(dian)放(fang)大(da)式檢(jian)(jian)流(liu)計(ji)。初級檢(jian)(jian)流(liu)計(ji)接(jie)在被測(ce)回路(lu)中，它的(de)(de)小鏡將(jiang)光線反射到差(cha)分光電(dian)池上。兩(liang)光電(dian)池的(de)(de)輸出(chu)電(dian)流(liu)之差(cha)流(liu)入次級檢(jian)(jian)流(liu)計(ji)G2。如此可(ke)獲得較強的(de)(de)信號(hao)。為(wei)使檢(jian)(jian)流(liu)計(ji)工作穩定，通(tong)常采(cai)用負反饋線路(lu)。
測(ce)(ce)短(duan)(duan)暫脈(mo)沖(chong)(chong)電(dian)(dian)(dian)(dian)流(liu)所含電(dian)(dian)(dian)(dian)荷(he)量(liang)的(de)(de)(de)(de)磁(ci)電(dian)(dian)(dian)(dian)系檢(jian)(jian)流(liu)計(ji)(ji)。其可(ke)動(dong)(dong)部(bu)分具有(you)較大(da)慣(guan)量(liang)。為保(bao)證測(ce)(ce)量(liang)準確度(du)，理論(lun)上(shang)(shang)要求在短(duan)(duan)暫脈(mo)沖(chong)(chong)電(dian)(dian)(dian)(dian)流(liu)通過(guo)檢(jian)(jian)流(liu)計(ji)(ji)時(shi)，可(ke)動(dong)(dong)部(bu)分應靜止不(bu)動(dong)(dong)；短(duan)(duan)暫脈(mo)沖(chong)(chong)消(xiao)失后(hou)(hou)，可(ke)動(dong)(dong)部(bu)分或單方向，或以刻度(du)零點為中心作衰減擺(bai)(bai)動(dong)(dong)。不(bu)論(lun)哪種情(qing)況，取(qu)大(da)偏轉(zhuan)或擺(bai)(bai)動(dong)(dong)的(de)(de)(de)(de)第一次(ci)大(da)值(zhi)(zhi)αm來表示(shi)電(dian)(dian)(dian)(dian)荷(he)量(liang)Q的(de)(de)(de)(de)大(da)小(xiao)，即αm=S,Sq是沖(chong)(chong)擊(ji)檢(jian)(jian)流(liu)計(ji)(ji)的(de)(de)(de)(de)沖(chong)(chong)擊(ji)靈敏度(du)。可(ke)通過(guo)接入(ru)光(guang)電(dian)(dian)(dian)(dian)放大(da)器來提高沖(chong)(chong)擊(ji)檢(jian)(jian)流(liu)計(ji)(ji)的(de)(de)(de)(de)Sq。普通磁(ci)電(dian)(dian)(dian)(dian)系檢(jian)(jian)流(liu)計(ji)(ji)也(ye)可(ke)用以測(ce)(ce)電(dian)(dian)(dian)(dian)荷(he)量(liang)，但其可(ke)動(dong)(dong)部(bu)分的(de)(de)(de)(de)慣(guan)量(liang)不(bu)夠大(da)，會(hui)產生測(ce)(ce)量(liang)誤(wu)差(cha)。一種動(dong)(dong)磁(ci)鐵(tie)式檢(jian)(jian)流(liu)計(ji)(ji)。可(ke)動(dong)(dong)部(bu)分由(you)小(xiao)塊永(yong)磁(ci)鐵(tie)和(he)小(xiao)鏡(jing)(jing)構(gou)成，其上(shang)(shang)下被張絲拉緊。小(xiao)磁(ci)鐵(tie)處于用疊片組(zu)成的(de)(de)(de)(de)磁(ci)極間，磁(ci)極上(shang)(shang)繞有(you)線(xian)圈(quan)，被檢(jian)(jian)測(ce)(ce)電(dian)(dian)(dian)(dian)流(liu)i通入(ru)此(ci)線(xian)圈(quan)后(hou)(hou),由(you)于可(ke)動(dong)(dong)部(bu)分的(de)(de)(de)(de)質量(liang)和(he)慣(guan)性都(dou)較小(xiao)，因此(ci),可(ke)動(dong)(dong)部(bu)分可(ke)跟隨(sui)電(dian)(dian)(dian)(dian)流(liu)i引起(qi)的(de)(de)(de)(de)交變(bian)磁(ci)場的(de)(de)(de)(de)瞬時(shi)值(zhi)(zhi)的(de)(de)(de)(de)變(bian)化動(dong)(dong)作。小(xiao)鏡(jing)(jing)左右(you)擺(bai)(bai)動(dong)(dong)，光(guang)線(xian)被小(xiao)鏡(jing)(jing)反射后(hou)(hou),在標尺上(shang)(shang)形(xing)成光(guang)帶。i為零時(shi),小(xiao)鏡(jing)(jing)不(bu)動(dong)(dong),光(guang)帶縮成一條線(xian)。??
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