一、電阻的種類有哪些

1、按伏安特性分類

可分(fen)為(wei)線(xian)(xian)性(xing)電阻和非(fei)線(xian)(xian)性(xing)電阻。對大多數(shu)導體(ti)來(lai)說，在一定的溫度下(xia)，其電阻幾乎維(wei)持不變而為(wei)一定值，這類(lei)電阻稱為(wei)線(xian)(xian)性(xing)電阻。

有些材料(liao)的(de)電(dian)(dian)(dian)阻(zu)(zu)(zu)明顯(xian)地隨著電(dian)(dian)(dian)流(liu)（或電(dian)(dian)(dian)壓(ya)）而變化，其伏安特(te)(te)性(xing)(xing)是一條曲線(xian)，這類電(dian)(dian)(dian)阻(zu)(zu)(zu)稱為(wei)非線(xian)性(xing)(xing)電(dian)(dian)(dian)阻(zu)(zu)(zu)。非線(xian)性(xing)(xing)電(dian)(dian)(dian)阻(zu)(zu)(zu)在(zai)某(mou)一給定(ding)的(de)電(dian)(dian)(dian)壓(ya)（或電(dian)(dian)(dian)流(liu)）作用(yong)(yong)下，電(dian)(dian)(dian)壓(ya)與(yu)電(dian)(dian)(dian)流(liu)的(de)比值為(wei)在(zai)該工作點下的(de)靜(jing)態電(dian)(dian)(dian)阻(zu)(zu)(zu)，伏安特(te)(te)性(xing)(xing)曲線(xian)上的(de)斜率為(wei)動態電(dian)(dian)(dian)阻(zu)(zu)(zu)。表達非線(xian)性(xing)(xing)電(dian)(dian)(dian)阻(zu)(zu)(zu)特(te)(te)性(xing)(xing)的(de)方式比較(jiao)復雜，但(dan)這些非線(xian)性(xing)(xing)關(guan)系(xi)在(zai)電(dian)(dian)(dian)子電(dian)(dian)(dian)路中得(de)到了(le)廣泛的(de)應(ying)用(yong)(yong)。

2、按材料分類

a.線繞(rao)電(dian)阻器由(you)電(dian)阻線繞(rao)成電(dian)阻器，用(yong)高(gao)阻合金線繞(rao)在絕(jue)(jue)緣(yuan)骨架上制成，外面涂有耐(nai)(nai)熱的釉絕(jue)(jue)緣(yuan)層(ceng)或絕(jue)(jue)緣(yuan)漆。繞(rao)線電(dian)阻具有較(jiao)低的溫度系數，阻值精度高(gao)，穩定性(xing)好，耐(nai)(nai)熱耐(nai)(nai)腐蝕，主要做精密(mi)大功率電(dian)阻使用(yong)，缺(que)點是高(gao)頻(pin)性(xing)能差，時間(jian)常數大。

b.碳合成(cheng)(cheng)電阻器由碳及合成(cheng)(cheng)塑膠壓制成(cheng)(cheng)而成(cheng)(cheng)。

c.碳膜電(dian)阻(zu)器在(zai)(zai)瓷(ci)管上(shang)鍍上(shang)一層碳而成，將(jiang)結晶(jing)碳沉(chen)積(ji)在(zai)(zai)陶瓷(ci)棒骨架上(shang)制成。碳膜電(dian)阻(zu)器成本低、性(xing)能穩定、阻(zu)值范(fan)圍寬、溫(wen)度系數和(he)電(dian)壓系數低，是(shi)目前(qian)應用最(zui)廣泛的(de)電(dian)阻(zu)器。

d.金(jin)屬膜(mo)電(dian)阻器在瓷(ci)管上(shang)鍍上(shang)一層(ceng)金(jin)屬而成(cheng)，用(yong)真空蒸(zheng)發的方法將合金(jin)材料(liao)蒸(zheng)鍍于陶瓷(ci)棒骨架表(biao)面。金(jin)屬膜(mo)電(dian)阻比碳膜(mo)電(dian)阻的精(jing)度(du)高，穩定性好(hao)，噪聲，溫度(du)系數(shu)小。在儀(yi)器儀(yi)表(biao)及通(tong)訊設(she)備(bei)中大量采(cai)用(yong)。

e.金(jin)屬氧(yang)(yang)化(hua)膜(mo)電(dian)阻器在(zai)(zai)瓷管上鍍上一層(ceng)氧(yang)(yang)化(hua)錫而成，在(zai)(zai)絕緣棒上沉積一層(ceng)金(jin)屬氧(yang)(yang)化(hua)物。由(you)于其(qi)本身即是(shi)氧(yang)(yang)化(hua)物，所以高(gao)(gao)(gao)溫(wen)下(xia)穩(wen)定，耐熱沖擊，負載能力強。按(an)用途分(fen)，有通用、精密、高(gao)(gao)(gao)頻、高(gao)(gao)(gao)壓、高(gao)(gao)(gao)阻、大功率和(he)電(dian)阻網絡等。

3、特殊電阻器

a.保險(xian)電(dian)阻(zu)：又叫熔斷電(dian)阻(zu)器，在正常情況(kuang)下(xia)起著(zhu)電(dian)阻(zu)和保險(xian)絲(si)(si)(si)的雙(shuang)重作用(yong)(yong)，當電(dian)路(lu)出現故障而使其功率(lv)超過額定功率(lv)時，它會像(xiang)保險(xian)絲(si)(si)(si)一樣熔斷使連接電(dian)路(lu)斷開(kai)。保險(xian)絲(si)(si)(si)電(dian)阻(zu)一般電(dian)阻(zu)值都(dou)小（0.33Ω～10KΩ），功率(lv)也較小。保險(xian)絲(si)(si)(si)電(dian)阻(zu)器常用(yong)(yong)型(xing)(xing)(xing)號有：RF10型(xing)(xing)(xing)、RF111-5保險(xian)絲(si)(si)(si)電(dian)阻(zu)器的符(fu)號型(xing)(xing)(xing)、RRD0910型(xing)(xing)(xing)、RRD0911型(xing)(xing)(xing)等。

b.敏(min)(min)感(gan)(gan)電(dian)(dian)(dian)阻(zu)(zu)器(qi)(qi)：是指其電(dian)(dian)(dian)阻(zu)(zu)值(zhi)對于某種物(wu)(wu)理量(liang)(liang)（如(ru)溫度(du)、濕度(du)、光(guang)照(zhao)、電(dian)(dian)(dian)壓(ya)、機械力、以及氣體(ti)濃度(du)等）具(ju)有(you)敏(min)(min)感(gan)(gan)特性，當(dang)這些物(wu)(wu)理量(liang)(liang)發生(sheng)變化時，敏(min)(min)感(gan)(gan)電(dian)(dian)(dian)阻(zu)(zu)的阻(zu)(zu)值(zhi)就會隨物(wu)(wu)理量(liang)(liang)變化而發生(sheng)改變，呈(cheng)現不同的電(dian)(dian)(dian)阻(zu)(zu)值(zhi)。根據對不同物(wu)(wu)理量(liang)(liang)敏(min)(min)感(gan)(gan)，敏(min)(min)感(gan)(gan)電(dian)(dian)(dian)阻(zu)(zu)器(qi)(qi)可分(fen)為熱敏(min)(min)、濕敏(min)(min)、光(guang)敏(min)(min)、壓(ya)敏(min)(min)、力敏(min)(min)、磁敏(min)(min)和氣敏(min)(min)等類(lei)型敏(min)(min)感(gan)(gan)電(dian)(dian)(dian)阻(zu)(zu)。敏(min)(min)感(gan)(gan)電(dian)(dian)(dian)阻(zu)(zu)器(qi)(qi)所用的材料幾乎(hu)都是半(ban)(ban)導(dao)體(ti)材料，這類(lei)電(dian)(dian)(dian)阻(zu)(zu)器(qi)(qi)也(ye)稱為半(ban)(ban)導(dao)體(ti)電(dian)(dian)(dian)阻(zu)(zu)器(qi)(qi)。

c.熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)的阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)值隨溫度(du)(du)變化(hua)而(er)變化(hua)，溫度(du)(du)升(sheng)高阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)為負(fu)(fu)溫度(du)(du)系(xi)數（NTC）熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)。應用較多的是負(fu)(fu)溫度(du)(du)系(xi)數熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)，又(you)可分(fen)為普通型(xing)負(fu)(fu)溫度(du)(du)系(xi)數熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)；穩壓型(xing)負(fu)(fu)溫度(du)(du)系(xi)數熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)；測溫型(xing)負(fu)(fu)溫度(du)(du)系(xi)數熱(re)(re)敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)等。光敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)是電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)的阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)值隨入(ru)射(she)光的強弱(ruo)變化(hua)而(er)改變，當入(ru)射(she)光增(zeng)強時，光敏(min)電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)的減小，入(ru)射(she)光減弱(ruo)時電(dian)(dian)(dian)阻(zu)(zu)(zu)(zu)(zu)(zu)(zu)值增(zeng)大。

該圖片由注冊用戶"天空之城"提供，版權聲明反饋

二、電阻器選用的方法

1、固定電阻器的選用

固(gu)定電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)有多種類型(xing)，選擇哪一種材料和(he)結構的電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，應(ying)根據應(ying)用電(dian)(dian)(dian)(dian)(dian)路(lu)的具(ju)體要求而定。高頻電(dian)(dian)(dian)(dian)(dian)路(lu)應(ying)選用分(fen)(fen)布電(dian)(dian)(dian)(dian)(dian)感和(he)分(fen)(fen)布電(dian)(dian)(dian)(dian)(dian)容小的非線(xian)繞電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，例(li)如碳(tan)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)、金屬(shu)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)和(he)金屬(shu)氧化(hua)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，薄(bo)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，厚膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，合金電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，防腐蝕鍍膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)等。高增益小信(xin)號放大電(dian)(dian)(dian)(dian)(dian)路(lu)應(ying)選用低噪(zao)聲電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，例(li)如金屬(shu)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)、碳(tan)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)和(he)線(xian)繞電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)，而不(bu)能(neng)使用噪(zao)聲較(jiao)大的合成碳(tan)膜電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)和(he)有機實心電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)(qi)(qi)(qi)。

所選電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)值應(ying)接(jie)近應(ying)用(yong)電(dian)(dian)路(lu)中計(ji)算值的(de)(de)一(yi)個(ge)標稱(cheng)值，應(ying)優先選用(yong)標準系列的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)。一(yi)般(ban)電(dian)(dian)路(lu)使(shi)用(yong)的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)允(yun)許誤差為±5%~±10%。精(jing)密(mi)儀器(qi)(qi)(qi)及特殊電(dian)(dian)路(lu)中使(shi)用(yong)的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)，應(ying)選用(yong)精(jing)密(mi)電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)，對精(jing)密(mi)度(du)為1%以內的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)，如0.01%，0.1%，0.5%這些(xie)量級(ji)的(de)(de)電(dian)(dian)阻(zu)(zu)(zu)應(ying)采(cai)用(yong)捷比信電(dian)(dian)阻(zu)(zu)(zu)。所選電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)的(de)(de)額定功率，要符合(he)應(ying)用(yong)電(dian)(dian)路(lu)中對電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)功率容量的(de)(de)要求，一(yi)般(ban)不(bu)應(ying)隨(sui)意加大或減小電(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)的(de)(de)功率。

若電(dian)路要求是(shi)功率型(xing)電(dian)阻器，則(ze)其額定功率可高于實(shi)際應(ying)用(yong)電(dian)路要求功率的1~2倍。

2、熔斷電阻器的選用

熔斷電(dian)阻器具(ju)有保(bao)護功(gong)(gong)(gong)能的(de)電(dian)阻器。選(xuan)用(yong)時(shi)應考(kao)慮(lv)其雙重(zhong)性(xing)能，根據電(dian)路的(de)具(ju)體要求選(xuan)擇(ze)其阻值(zhi)和功(gong)(gong)(gong)率等(deng)參數。既要保(bao)證它在過(guo)(guo)負荷時(shi)能快(kuai)速熔斷，又要保(bao)證它在正常條件下能長期(qi)穩(wen)定的(de)工作。電(dian)阻值(zhi)過(guo)(guo)大(da)或功(gong)(gong)(gong)率過(guo)(guo)大(da)，均不(bu)能起到保(bao)護作用(yong)。

三、電阻器選用的基本原則

1、選擇通(tong)過認(ren)證機構認(ren)證的生產(chan)線制造出的執行高水平(ping)標準的電阻器。

2、選擇(ze)具備(bei)功能優勢(shi)、質量優勢(shi)、效(xiao)率(lv)優勢(shi)、功能價格比(bi)優勢(shi)、服務(wu)優勢(shi)的(de)制造商生產的(de)電阻器。

3、選擇能滿足上述要求的上型號目錄的制造商，并向其直接訂購電阻器。