【電(dian)阻的作用(yong)】電(dian)阻在電(dian)路中有什么作用(yong) 電(dian)阻器(qi)有哪些分類

電阻在電路中有什么作用

電阻器在日常生活中一般直接稱為電阻?是(shi)(shi)一個(ge)限流(liu)元件,將電(dian)阻(zu)(zu)(zu)(zu)(zu)接在(zai)電(dian)路中后,電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)的(de)(de)(de)(de)(de)(de)阻(zu)(zu)(zu)(zu)(zu)值是(shi)(shi)固(gu)(gu)定的(de)(de)(de)(de)(de)(de)一般是(shi)(shi)兩個(ge)引腳,它可(ke)限制通過(guo)它所連支路的(de)(de)(de)(de)(de)(de)電(dian)流(liu)大小(xiao)?阻(zu)(zu)(zu)(zu)(zu)值不能改(gai)變的(de)(de)(de)(de)(de)(de)稱為(wei)(wei)固(gu)(gu)定電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)?阻(zu)(zu)(zu)(zu)(zu)值可(ke)變的(de)(de)(de)(de)(de)(de)稱為(wei)(wei)電(dian)位(wei)器(qi)或可(ke)變電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)?理(li)想的(de)(de)(de)(de)(de)(de)電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)是(shi)(shi)線性的(de)(de)(de)(de)(de)(de),即通過(guo)電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)的(de)(de)(de)(de)(de)(de)瞬時(shi)(shi)電(dian)流(liu)與(yu)外加瞬時(shi)(shi)電(dian)壓成正比?用于(yu)分壓的(de)(de)(de)(de)(de)(de)可(ke)變電(dian)阻(zu)(zu)(zu)(zu)(zu)器(qi)?在(zai)裸(luo)露(lu)的(de)(de)(de)(de)(de)(de)電(dian)阻(zu)(zu)(zu)(zu)(zu)體(ti)上,緊(jin)壓著一至兩個(ge)可(ke)移金(jin)屬觸(chu)點?觸(chu)點位(wei)置確定電(dian)阻(zu)(zu)(zu)(zu)(zu)體(ti)任一端與(yu)觸(chu)點間的(de)(de)(de)(de)(de)(de)阻(zu)(zu)(zu)(zu)(zu)值?

該圖片由注冊用戶"橘子de殿堂"提供，版權聲明反饋

小功率(lv)電阻(zu)器通(tong)常為封裝在塑料(liao)外殼中的(de)(de)碳膜構成,而大功率(lv)的(de)(de)電阻(zu)器通(tong)常為繞線電阻(zu)器,通(tong)過將大電阻(zu)率(lv)的(de)(de)金(jin)屬絲繞在瓷心上而制(zhi)成?

如果一(yi)個電(dian)(dian)阻(zu)(zu)器(qi)的(de)電(dian)(dian)阻(zu)(zu)值接近(jin)零歐姆,則該(gai)電(dian)(dian)阻(zu)(zu)器(qi)對(dui)電(dian)(dian)流(liu)(liu)(liu)沒有(you)阻(zu)(zu)礙(ai)作(zuo)用(yong),并聯這種電(dian)(dian)阻(zu)(zu)器(qi)的(de)回路(lu)(lu)被(bei)短路(lu)(lu),電(dian)(dian)流(liu)(liu)(liu)無限大(da)?如果一(yi)個電(dian)(dian)阻(zu)(zu)器(qi)具(ju)有(you)無限大(da)的(de)或(huo)很大(da)的(de)電(dian)(dian)阻(zu)(zu),則串接該(gai)電(dian)(dian)阻(zu)(zu)器(qi)的(de)回路(lu)(lu)可看(kan)作(zuo)開路(lu)(lu),電(dian)(dian)流(liu)(liu)(liu)為零?工業中常用(yong)的(de)電(dian)(dian)阻(zu)(zu)器(qi)介(jie)于(yu)兩種極(ji)端情(qing)況之(zhi)間,它(ta)具(ju)有(you)一(yi)定的(de)電(dian)(dian)阻(zu)(zu),可通過(guo)一(yi)定的(de)電(dian)(dian)流(liu)(liu)(liu),但電(dian)(dian)流(liu)(liu)(liu)不(bu)像短路(lu)(lu)時那樣大(da)?電(dian)(dian)阻(zu)(zu)器(qi)的(de)限流(liu)(liu)(liu)作(zuo)用(yong)類似于(yu)接在兩根(gen)大(da)直(zhi)徑(jing)管子之(zhi)間的(de)小直(zhi)徑(jing)管子限制水流(liu)(liu)(liu)量的(de)作(zuo)用(yong)?

電阻器有哪些分類

按伏安特性分類

對大多數導體來說,在一定的溫度下,其電阻幾乎維持不變而為(wei)(wei)(wei)一(yi)定(ding)值(zhi),這(zhe)類電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)稱(cheng)為(wei)(wei)(wei)線(xian)(xian)(xian)性電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)?有些(xie)材料(liao)的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)明(ming)顯地隨著電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(或電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya))而變化(hua),其伏(fu)(fu)—安特(te)(te)性是一(yi)條曲(qu)線(xian)(xian)(xian),這(zhe)類電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)稱(cheng)為(wei)(wei)(wei)非(fei)(fei)線(xian)(xian)(xian)性電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)?非(fei)(fei)線(xian)(xian)(xian)性電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)在某一(yi)給定(ding)的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(或電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流)作用下,電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)與(yu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流的比(bi)值(zhi)為(wei)(wei)(wei)在該工作點下的靜態(tai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu),伏(fu)(fu)—安特(te)(te)性曲(qu)線(xian)(xian)(xian)上的斜率為(wei)(wei)(wei)動態(tai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)?表(biao)達非(fei)(fei)線(xian)(xian)(xian)性電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)特(te)(te)性的方式比(bi)較(jiao)復雜,但這(zhe)些(xie)非(fei)(fei)線(xian)(xian)(xian)性關系在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路中得到了廣泛的應用?

按材料分類

a?線(xian)(xian)繞(rao)(rao)電(dian)(dian)阻器(qi)由電(dian)(dian)阻線(xian)(xian)繞(rao)(rao)成(cheng)(cheng)電(dian)(dian)阻器(qi) 用高(gao)阻合金線(xian)(xian)繞(rao)(rao)在絕緣(yuan)骨架上(shang)制成(cheng)(cheng),外面涂有耐熱的(de)釉絕緣(yuan)層或絕緣(yuan)漆?繞(rao)(rao)線(xian)(xian)電(dian)(dian)阻具有較低的(de)溫度系數,阻值精度高(gao),穩定性好,耐熱耐腐蝕,主要做精密大功率電(dian)(dian)阻使用,缺點是高(gao)頻性能(neng)差,時間常數大?

b?碳(tan)合成(cheng)電阻器由碳(tan)及合成(cheng)塑膠壓制成(cheng)而成(cheng)?

c?碳膜電阻器在(zai)瓷管上鍍(du)上一(yi)層碳而(er)成,將結晶碳沉積在(zai)陶瓷棒(bang)骨架(jia)上制成?碳膜電阻器成本低?性能(neng)穩定?阻值范圍寬?溫度系(xi)數(shu)和電壓系(xi)數(shu)低,是目前應用(yong)最廣泛(fan)的電阻器?

d?金(jin)屬膜電阻器在瓷(ci)(ci)管上鍍(du)上一層金(jin)屬而(er)成,用真空蒸發的(de)方法將合金(jin)材料(liao)蒸鍍(du)于陶瓷(ci)(ci)棒(bang)骨架(jia)表面?

金屬膜電(dian)阻比碳膜電(dian)阻的精度高(gao),穩定性好(hao),噪聲(sheng),溫度系數小?在儀(yi)器儀(yi)表及(ji)通訊(xun)設備中大量(liang)采用?

e?金屬氧化膜電阻器在瓷管上鍍上一層(ceng)氧化(hua)錫而成,在絕(jue)緣棒上沉積(ji)一層(ceng)金屬氧化(hua)物?由于(yu)其本身即是氧化(hua)物,所以高(gao)溫(wen)下穩定(ding),耐熱沖擊,負載能力強(qiang) 按用途分,有(you)通(tong)用?精密(mi)?高(gao)頻?高(gao)壓?高(gao)阻?大功率和電阻網絡等?

特殊電阻器

1?保(bao)(bao)險電(dian)(dian)阻(zu):又叫熔(rong)斷(duan)電(dian)(dian)阻(zu)器(qi),在正常情況下起著(zhu)電(dian)(dian)阻(zu)和保(bao)(bao)險絲(si)的雙重作(zuo)用,當電(dian)(dian)路出(chu)現故障而(er)使其功(gong)(gong)率(lv)超過(guo)額定功(gong)(gong)率(lv)時,它會像保(bao)(bao)險絲(si)一樣熔(rong)斷(duan)使連接電(dian)(dian)路斷(duan)開?保(bao)(bao)險絲(si)電(dian)(dian)阻(zu)一般電(dian)(dian)阻(zu)值(zhi)都小(0.33Ω~10KΩ),功(gong)(gong)率(lv)也較小?保(bao)(bao)險絲(si)電(dian)(dian)阻(zu)器(qi)常用型(xing)(xing)號有(you):RF10型(xing)(xing)?RF111-5保(bao)(bao)險絲(si)電(dian)(dian)阻(zu)器(qi)的符號型(xing)(xing)?RRD0910型(xing)(xing)?RRD0911型(xing)(xing)等?

2?敏(min)(min)(min)感電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi):是指其電(dian)(dian)阻(zu)(zu)(zu)值(zhi)對(dui)于某種(zhong)物理(li)量(liang)(如溫度(du)?濕度(du)?光照?電(dian)(dian)壓?機械力(li)?以及(ji)氣(qi)體(ti)濃度(du)等)具有敏(min)(min)(min)感特性,當這些物理(li)量(liang)發(fa)生變(bian)化時,敏(min)(min)(min)感電(dian)(dian)阻(zu)(zu)(zu)的阻(zu)(zu)(zu)值(zhi)就會隨(sui)物理(li)量(liang)變(bian)化而(er)發(fa)生改變(bian),呈現不(bu)同的電(dian)(dian)阻(zu)(zu)(zu)值(zhi)?根據對(dui)不(bu)同物理(li)量(liang)敏(min)(min)(min)感,敏(min)(min)(min)感電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)可分為熱敏(min)(min)(min)?濕敏(min)(min)(min)?光敏(min)(min)(min)?壓敏(min)(min)(min)?力(li)敏(min)(min)(min)?磁敏(min)(min)(min)和氣(qi)敏(min)(min)(min)等類(lei)(lei)型敏(min)(min)(min)感電(dian)(dian)阻(zu)(zu)(zu)?敏(min)(min)(min)感電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)所(suo)用的材料幾(ji)乎都是半導(dao)(dao)體(ti)材料,這類(lei)(lei)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)也稱為半導(dao)(dao)體(ti)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)?

熱敏電阻的(de)阻(zu)(zu)(zu)值隨溫(wen)(wen)度(du)(du)變化而(er)變化,溫(wen)(wen)度(du)(du)升高阻(zu)(zu)(zu)為(wei)負(fu)溫(wen)(wen)度(du)(du)系(xi)數(shu)(shu)(NTC)熱(re)敏(min)電(dian)(dian)阻(zu)(zu)(zu)?應(ying)用較多的(de)是(shi)負(fu)溫(wen)(wen)度(du)(du)系(xi)數(shu)(shu)熱(re)敏(min)電(dian)(dian)阻(zu)(zu)(zu),又可分為(wei)普通(tong)型負(fu)溫(wen)(wen)度(du)(du)系(xi)數(shu)(shu)熱(re)敏(min)電(dian)(dian)阻(zu)(zu)(zu);穩壓型負(fu)溫(wen)(wen)度(du)(du)系(xi)數(shu)(shu)熱(re)敏(min)電(dian)(dian)阻(zu)(zu)(zu);測溫(wen)(wen)型負(fu)溫(wen)(wen)度(du)(du)系(xi)數(shu)(shu)熱(re)敏(min)電(dian)(dian)阻(zu)(zu)(zu)等? 光(guang)敏(min)電(dian)(dian)阻(zu)(zu)(zu)是(shi)電(dian)(dian)阻(zu)(zu)(zu)的(de)阻(zu)(zu)(zu)值隨入(ru)射光(guang)的(de)強弱變化而(er)改變,當入(ru)射光(guang)增強時(shi),光(guang)敏(min)電(dian)(dian)阻(zu)(zu)(zu)的(de)減小,入(ru)射光(guang)減弱時(shi)電(dian)(dian)阻(zu)(zu)(zu)值增大?