防爆電子天平  上海電子秤

關于電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)的(de)(de)(de)(de)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)方法(fa)(fa)(使用前(qian)一(yi)定要(yao)仔細閱讀說(shuo)明(ming)書(shu))，在(zai)檢(jian)定(測(ce)試(shi))中我們發現(xian)(xian)(xian)，對天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)進(jin)(jin)行(xing)*計量(liang)測(ce)試(shi)時(shi)(shi)(shi)誤(wu)差較(jiao)大(da)(da)，究(jiu)其(qi)(qi)(qi)原(yuan)因(yin)，相當(dang)(dang)(dang)一(yi)部分儀(yi)器，在(zai)較(jiao)長(chang)的(de)(de)(de)(de)時(shi)(shi)(shi)間間隔內(nei)未(wei)進(jin)(jin)行(xing)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)，而且認為(wei)(wei)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)顯示(shi)零(ling)位(wei)便(bian)可直(zhi)(zhi)接稱(cheng)量(liang)。(需要(yao)指(zhi)出(chu)的(de)(de)(de)(de)是(shi)，電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)開(kai)機顯示(shi)零(ling)點，不(bu)能說(shuo)明(ming)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)稱(cheng)量(liang)的(de)(de)(de)(de)數據準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)確(que)(que)度(du)符(fu)合測(ce)試(shi)標(biao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)，只(zhi)能說(shuo)明(ming)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)零(ling)位(wei)穩定性(xing)合格(ge)。因(yin)為(wei)(wei)衡(heng)量(liang)一(yi)臺天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)合格(ge)與否，還需綜合考慮(lv)其(qi)(qi)(qi)它技術指(zhi)標(biao)的(de)(de)(de)(de)符(fu)合性(xing))。因(yin)存放時(shi)(shi)(shi)間較(jiao)長(chang)，位(wei)置(zhi)移動(dong)(dong)(dong)，環(huan)境變(bian)化或為(wei)(wei)獲(huo)得精確(que)(que)測(ce)量(liang)，天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)在(zai)使用前(qian)一(yi)般都(dou)應進(jin)(jin)行(xing)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)操(cao)作(zuo)。校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)方法(fa)(fa)分為(wei)(wei)內(nei)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)和外校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)兩種(zhong)。德國生產的(de)(de)(de)(de)賽多利斯，瑞(rui)士(shi)產的(de)(de)(de)(de)梅特勒，上(shang)海產的(de)(de)(de)(de)"JA"等(deng)(deng)系列電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)均有校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)裝(zhuang)置(zhi)。如(ru)(ru)果使用前(qian)不(bu)仔細閱讀說(shuo)明(ming)書(shu)很容易忽(hu)略"校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)"操(cao)作(zuo)，造成(cheng)較(jiao)大(da)(da)稱(cheng)量(liang)誤(wu)差。下(xia)面以上(shang)海天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)儀(yi)器廠(chang)JA1203型電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)為(wei)(wei)例說(shuo)明(ming)如(ru)(ru)何對天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)進(jin)(jin)行(xing)外校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)。方法(fa)(fa):輕按(an)(an)CAL鍵當(dang)(dang)(dang)顯示(shi)器出(chu)現(xian)(xian)(xian)CAL-時(shi)(shi)(shi)，即(ji)松手，顯示(shi)器就出(chu)現(xian)(xian)(xian)CAL-100其(qi)(qi)(qi)中"100"為(wei)(wei)閃爍碼(ma)(ma)(ma)，表示(shi)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)砝(fa)(fa)(fa)碼(ma)(ma)(ma)需用100g的(de)(de)(de)(de)標(biao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)砝(fa)(fa)(fa)碼(ma)(ma)(ma)。此時(shi)(shi)(shi)就把準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)備(bei)好"100g"校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)砝(fa)(fa)(fa)碼(ma)(ma)(ma)放上(shang)稱(cheng)盤(pan)，顯示(shi)器即(ji)出(chu)現(xian)(xian)(xian)"----"等(deng)(deng)待(dai)狀(zhuang)態，經較(jiao)長(chang)時(shi)(shi)(shi)間后顯示(shi)器出(chu)現(xian)(xian)(xian)100.000g，拿去校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)砝(fa)(fa)(fa)碼(ma)(ma)(ma)，顯示(shi)器應出(chu)現(xian)(xian)(xian)0.000g，若(ruo)出(chu)現(xian)(xian)(xian)不(bu)是(shi)為(wei)(wei)零(ling)，則再清(qing)零(ling)，再重(zhong)復(fu)以上(shang)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)操(cao)作(zuo)(注(zhu)意:為(wei)(wei)了得到準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)確(que)(que)的(de)(de)(de)(de)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)結果重(zhong)復(fu)以上(shang)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)操(cao)作(zuo)步驟兩次)。以瑞(rui)士(shi)MettlerToledo AG系列電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)為(wei)(wei)例說(shuo)明(ming)如(ru)(ru)何進(jin)(jin)行(xing)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)內(nei)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)。方法(fa)(fa)如(ru)(ru)下(xia):天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)置(zhi)零(ling)位(wei)，然后持(chi)續按(an)(an)住"CAL"鍵直(zhi)(zhi)到CAL int出(chu)現(xian)(xian)(xian)為(wei)(wei)止，下(xia)述(shu)情況將在(zai)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)時(shi)(shi)(shi)顯示(shi):天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)置(zhi)零(ling)、內(nei)部校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)砝(fa)(fa)(fa)碼(ma)(ma)(ma)裝(zhuang)載完畢、天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)重(zhong)新檢(jian)查零(ling)位(wei)、天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)報告(gao)(gao)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)過(guo)程、天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)報告(gao)(gao)校(xiao)(xiao)(xiao)(xiao)(xiao)(xiao)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)完畢、天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)自動(dong)(dong)(dong)回復(fu)到稱(cheng)重(zhong)狀(zhuang)態。1、有的(de)(de)(de)(de)人(ren)認為(wei)(wei)在(zai)電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)量(liang)程范(fan)圍(wei)(wei)內(nei)稱(cheng)量(liang)的(de)(de)(de)(de)物(wu)體越重(zhong)對天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)的(de)(de)(de)(de)損(sun)害(hai)也就越大(da)(da)。這種(zhong)認識是(shi)不(bu)*正(zheng)確(que)(que)的(de)(de)(de)(de)。一(yi)般衡(heng)器大(da)(da)安全載荷是(shi)它所能夠承受(shou)的(de)(de)(de)(de)、不(bu)致使其(qi)(qi)(qi)計量(liang)性(xing)能發生改變(bian)的(de)(de)(de)(de)大(da)(da)靜載荷。由于電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)采用了電(dian)(dian)(dian)(dian)(dian)磁(ci)力(li)(li)(li)自動(dong)(dong)(dong)補償(chang)電(dian)(dian)(dian)(dian)(dian)路(lu)原(yuan)理，當(dang)(dang)(dang)秤(cheng)盤(pan)加載時(shi)(shi)(shi)(注(zhu)意不(bu)要(yao)超過(guo)稱(cheng)量(liang)范(fan)圍(wei)(wei))，電(dian)(dian)(dian)(dian)(dian)磁(ci)力(li)(li)(li)會(hui)將秤(cheng)盤(pan)推回到原(yuan)來的(de)(de)(de)(de)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)位(wei)置(zhi)，使電(dian)(dian)(dian)(dian)(dian)磁(ci)力(li)(li)(li)與被稱(cheng)物(wu)體的(de)(de)(de)(de)重(zhong)力(li)(li)(li)相平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)，只(zhi)要(yao)在(zai)允許(xu)范(fan)圍(wei)(wei)內(nei)稱(cheng)量(liang)大(da)(da)小對天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)的(de)(de)(de)(de)影響(xiang)是(shi)很小的(de)(de)(de)(de)，不(bu)會(hui)因(yin)長(chang)期稱(cheng)重(zhong)而影響(xiang)電(dian)(dian)(dian)(dian)(dian)子(zi)天(tian)(tian)(tian)(tian)(tian)(tian)(tian)平(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)(ping)的(de)(de)(de)(de)準(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)(zhun)確(que)(que)度(du)。

選購

電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)如何(he)選(xuan)擇(ze)電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)?選(xuan)擇(ze)電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)應該從電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)的(de)(de)(de)精(jing)度(du)(分(fen)(fen)度(du)值(zhi)(zhi)e)上(shang)去考慮(lv)是(shi)否符(fu)合(he)稱(cheng)(cheng)量的(de)(de)(de)精(jing)度(du)要求。如選(xuan)0.1mg精(jing)度(du)的(de)(de)(de)天(tian)(tian)(tian)平(ping)(ping)或0.01mg精(jing)度(du)的(de)(de)(de)天(tian)(tian)(tian)平(ping)(ping)，切忌(ji)不(bu)可籠統地說要萬分(fen)(fen)之(zhi)一(yi)(yi)(yi)或十萬分(fen)(fen)之(zhi)一(yi)(yi)(yi)精(jing)度(du)的(de)(de)(de)天(tian)(tian)(tian)平(ping)(ping)，因(yin)為(wei)國外有些廠家是(shi)用(yong)(yong)(yong)相(xiang)對精(jing)度(du)來衡量天(tian)(tian)(tian)平(ping)(ping)的(de)(de)(de)，否則買來的(de)(de)(de)天(tian)(tian)(tian)平(ping)(ping)無法滿足用(yong)(yong)(yong)戶的(de)(de)(de)需要。例如在實(shi)際工作中遇到這(zhe)樣一(yi)(yi)(yi)個(ge)情(qing)況，用(yong)(yong)(yong)一(yi)(yi)(yi)臺(tai)實(shi)際標尺(chi)分(fen)(fen)度(du)值(zhi)(zhi)d為(wei)1mg，檢定標尺(chi)分(fen)(fen)度(du)值(zhi)(zhi)e為(wei)10mg，大(da)稱(cheng)(cheng)量為(wei)200g的(de)(de)(de)Mettler電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)，用(yong)(yong)(yong)來稱(cheng)(cheng)量7mg的(de)(de)(de)物體，這(zhe)樣是(shi)不(bu)能得出準(zhun)確結(jie)果的(de)(de)(de):在《JJG98-90非自動天(tian)(tian)(tian)平(ping)(ping)試行檢定規(gui)程(cheng)》中規(gui)定，大(da)允(yun)許(xu)誤(wu)差(cha)(cha)與檢定標尺(chi)分(fen)(fen)度(du)值(zhi)(zhi)"e"為(wei)同一(yi)(yi)(yi)數(shu)量級，此(ci)臺(tai)天(tian)(tian)(tian)平(ping)(ping)的(de)(de)(de)大(da)允(yun)許(xu)誤(wu)差(cha)(cha)為(wei)1e，顯然不(bu)能稱(cheng)(cheng)量7mg的(de)(de)(de)物體;稱(cheng)(cheng)量15mg的(de)(de)(de)物體用(yong)(yong)(yong)此(ci)類天(tian)(tian)(tian)平(ping)(ping)也(ye)不(bu)是(shi)選(xuan)擇(ze)，因(yin)為(wei)其測試結(jie)果的(de)(de)(de)相(xiang)對誤(wu)差(cha)(cha)會很大(da)，應選(xuan)擇(ze)更(geng)高(gao)一(yi)(yi)(yi)級的(de)(de)(de)天(tian)(tian)(tian)平(ping)(ping)，有的(de)(de)(de)廠家在出廠時已(yi)規(gui)定了小(xiao)稱(cheng)(cheng)量的(de)(de)(de)數(shu)值(zhi)(zhi)。因(yin)此(ci)我(wo)們在選(xuan)購及(ji)使用(yong)(yong)(yong)電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)時必須考慮(lv)精(jing)度(du)等級。⑵對稱(cheng)(cheng)量范圍的(de)(de)(de)要求:選(xuan)擇(ze)電(dian)子(zi)天(tian)(tian)(tian)平(ping)(ping)除了看(kan)其精(jing)度(du)，還應看(kan)大(da)稱(cheng)(cheng)量是(shi)否滿足量程(cheng)的(de)(de)(de)需要。通常(chang)取大(da)載(zai)荷加少許(xu)保險系數(shu)即(ji)可，也(ye)就是(shi)常(chang)用(yong)(yong)(yong)載(zai)荷再放寬一(yi)(yi)(yi)些即(ji)可，不(bu)是(shi)越大(da)越好。

結構原理(li)

衡(heng)器(qi)儀表是指(zhi)電(dian)子(zi)衡(heng)器(qi)中顯示(shi)被稱物的質量(liang)和稱量(liang)狀(zhuang)態的儀表，也叫稱重(zhong)顯示(shi)器(qi)。電(dian)子(zi)衡(heng)器(qi)儀表原(yuan)為(wei)模(mo)擬指(zhi)示(shi)式，由(you)誤(wu)差放(fang)大器(qi)、可逆電(dian)機、平衡(heng)電(dian)橋、激(ji)勵電(dian)源、度(du)盤(pan)和指(zhi)針(zhen)等部分組成，按自(zi)動平衡(heng)電(dian)子(zi)電(dian)位(wei)差計原(yuan)理工作。它稱量(liang)速度(du)慢，功能單(dan)一，準確度(du)低，現已基本被淘汰。現用稱重(zhong)顯示(shi)器(qi)為(wei)數字顯示(shi)式。

電(dian)子(zi)衡器(qi)儀表的構(gou)成電(dian)子(zi)天平(ping)

數(shu)字(zi)顯(xian)示(shi)(shi)式(shi)衡器(qi)儀表的(de)(de)(de)品(pin)種很多,圖1所示(shi)(shi)是(shi)其中(zhong)的(de)(de)(de)一(yi)(yi)種。數(shu)顯(xian)器(qi)接(jie)受處(chu)理(li)的(de)(de)(de)是(shi)稱(cheng)重傳(chuan)感器(qi)輸(shu)出的(de)(de)(de)電信(xin)號。電信(xin)號有模擬量(liang)(liang)也有數(shu)字(zi)量(liang)(liang)，常見的(de)(de)(de)是(shi)幾(ji)至幾(ji)十毫伏的(de)(de)(de)模擬電壓(ya)。數(shu)顯(xian)器(qi)的(de)(de)(de)電路原理(li)如圖2所示(shi)(shi)。激勵電源(yuan)供給(gei)稱(cheng)重傳(chuan)感器(qi)工(gong)作(zuo)(zuo)電源(yuan)，同時供給(gei)A/D(模/數(shu))轉(zhuan)(zhuan)換單(dan)元(yuan)基準(zhun)電壓(ya),其穩定度一(yi)(yi)般在(zai)0.1%以(yi)(yi)上(shang)。放(fang)(fang)(fang)大單(dan)元(yuan)通(tong)(tong)常采用測量(liang)(liang)放(fang)(fang)(fang)大器(qi)結構，接(jie)受、放(fang)(fang)(fang)大稱(cheng)重傳(chuan)感器(qi)的(de)(de)(de)信(xin)號。放(fang)(fang)(fang)大倍(bei)數(shu)一(yi)(yi)般為數(shu)百倍(bei)。濾(lv)波(bo)單(dan)元(yuan)濾(lv)掉從(cong)機外混入的(de)(de)(de)和放(fang)(fang)(fang)大器(qi)自身產生的(de)(de)(de)電噪聲。A/D轉(zhuan)(zhuan)換單(dan)元(yuan)把模擬量(liang)(liang)轉(zhuan)(zhuan)換成數(shu)字(zi)量(liang)(liang),轉(zhuan)(zhuan)換位數(shu)通(tong)(tong)常取二進制數(shu)14位以(yi)(yi)上(shang)。數(shu)據(ju)處(chu)理(li)單(dan)元(yuan)是(shi)以(yi)(yi)微處(chu)理(li)器(qi)為核心，使用外圍支持芯片(pian)組成的(de)(de)(de)，它在(zai)程序(xu)的(de)(de)(de)控制下完(wan)成采集數(shu)據(ju)、運算(suan)、存貯等一(yi)(yi)系列操作(zuo)(zuo)，處(chu)理(li)結果送到相應(ying)接(jie)口(kou)上(shang)。顯(xian)示(shi)(shi)單(dan)元(yuan)以(yi)(yi)數(shu)字(zi)或文字(zi)、圖表等形式(shi)顯(xian)示(shi)(shi)出稱(cheng)量(liang)(liang)值和稱(cheng)量(liang)(liang)狀態，并(bing)可通(tong)(tong)過(guo)接(jie)口(kou)與(yu)外部設(she)備聯絡。

數顯衡器(qi)儀(yi)(yi)表(biao)的(de)性能(neng)包括計量(liang)性能(neng)、功能(neng)、環(huan)境適應(ying)能(neng)力、安(an)全性和可靠性5個(ge)方(fang)(fang)面(mian)。與通用的(de)數字衡器(qi)稱重儀(yi)(yi)表(biao)相比,數顯器(qi)具有5個(ge)特(te)點:①自帶傳感器(qi)激勵電源，使用方(fang)(fang)便(bian);②采(cai)用比率型A/D轉換和倍(bei)頻技術,計量(liang)性能(neng)中的(de)長期穩(wen)定(ding)性好;水(shui)分(fen)測(ce)(ce)量(liang)儀(yi)(yi)，紅外線水(shui)分(fen)儀(yi)(yi)，水(shui)分(fen)測(ce)(ce)定(ding)儀(yi)(yi)，水(shui)分(fen)測(ce)(ce)試儀(yi)(yi)，水(shui)分(fen)檢測(ce)(ce)儀(yi)(yi)，水(shui)分(fen)測(ce)(ce)試儀(yi)(yi)，含水(shui)率測(ce)(ce)試儀(yi)(yi)，③軟(ruan)件(jian)能(neng)真(zhen)切地仿真(zhen)振動(dong)、空秤(cheng)變動(dong)、物(wu)料(liao)落(luo)差(cha)等稱量(liang)特(te)征，顯示快、準、穩(wen);④機(ji)內有空秤(cheng)置(zhi)零(ling)、零(ling)點跟蹤、定(ding)標(biao)、大秤(cheng)量(liang)、分(fen)度位等參數的(de)設定(ding)單(dan)元，改定(ding)方(fang)(fang)便(bian)，通用性強;⑤帶輸出接口(kou)，能(neng)夠聯接多(duo)種(zhong)外部設備(bei)，方(fang)(fang)便(bian)地實現系(xi)統(tong)控(kong)制。

準確度(du)(du)等(deng)級(ji)法制計量組織(OIML)3號(hao)建議(yi)規定，非(fei)自動(dong)衡(heng)(heng)(heng)(heng)器(qi)按(an)(an)準確度(du)(du)級(ji)別(bie)劃分(fen)(fen)為4個(ge)(ge)等(deng)級(ji)。按(an)(an)配用衡(heng)(heng)(heng)(heng)器(qi)的(de)(de)級(ji)別(bie)，中國將電子衡(heng)(heng)(heng)(heng)器(qi)儀表也劃分(fen)(fen)為4個(ge)(ge)等(deng)級(ji),并分(fen)(fen)別(bie)冠以與電子衡(heng)(heng)(heng)(heng)器(qi)對(dui)應的(de)(de)級(ji)別(bie)代號(hao):Ⅰ、Ⅱ、Ⅲ、Ⅳ。每個(ge)(ge)級(ji)別(bie)的(de)(de)衡(heng)(heng)(heng)(heng)器(qi)儀表的(de)(de)計量大允許(xu)誤(wu)差為對(dui)應級(ji)別(bie)衡(heng)(heng)(heng)(heng)器(qi)允許(xu)誤(wu)差的(de)(de)0.7倍。

儀(yi)(yi)(yi)表(biao)(biao)架構其實(shi)很(hen)簡單，一(yi)(yi)個電(dian)(dian)源(yuan)為(wei)全(quan)部器件供電(dian)(dian)，一(yi)(yi)個AD部分負責將傳感器的模擬信號放大，模數(shu)轉(zhuan)換到(dao)數(shu)字信號，一(yi)(yi)個中央處理器，也就是常說的單片機(MCU)，來處理AD部分讀(du)取到(dao)的重(zhong)量信號，進(jin)行一(yi)(yi)系列(lie)的換算(suan)處理，譯碼為(wei)可顯(xian)示閱讀(du)的信號，顯(xian)示在顯(xian)示屏(ping)上，同(tong)時(shi)一(yi)(yi)般(ban)還(huan)有(you)鍵盤(pan)電(dian)(dian)路，來接(jie)(jie)受用戶的一(yi)(yi)些操控，很(hen)多儀(yi)(yi)(yi)表(biao)(biao)還(huan)帶(dai)(dai)有(you)并行打印口(kou)(kou)(kou)(kou)，微打驅動(dong)，RS232或RS485接(jie)(jie)口(kou)(kou)(kou)(kou)與上位機或其它(ta)儀(yi)(yi)(yi)表(biao)(biao)互聯通訊，還(huan)有(you)數(shu)字電(dian)(dian)流環(huan)接(jie)(jie)口(kou)(kou)(kou)(kou)，以連接(jie)(jie)大屏(ping)幕(mu)，另(ling)外工(gong)業控制(zhi)用的很(hen)多儀(yi)(yi)(yi)表(biao)(biao)帶(dai)(dai)有(you)4~20mA電(dian)(dian)流環(huan)接(jie)(jie)口(kou)(kou)(kou)(kou)，以配接(jie)(jie)PLC。高(gao)檔的還(huan)有(you)現場CAN總線或者以太網接(jie)(jie)口(kou)(kou)(kou)(kou)，某些儀(yi)(yi)(yi)表(biao)(biao)還(huan)有(you)USB接(jie)(jie)口(kou)(kou)(kou)(kou)，不過(guo)USB由(you)于(yu)傳輸距離太近，在衡器儀(yi)(yi)(yi)表(biao)(biao)上用途較(jiao)少，因此也很(hen)少有(you)儀(yi)(yi)(yi)表(biao)(biao)有(you)USB接(jie)(jie)口(kou)(kou)(kou)(kou)。

防爆電子天平  上海電子秤