熔斷電阻器又稱保險電阻，它是一種兼具電阻器和熔斷器雙重功能的元件。在電路正常工作時，熔斷電阻器在額定功率下發出的熱量與周圍介質達到平衡，它具有電阻器的功能;當電路出現異常過載超過其額定功率時，它就會像保險絲一樣熔斷，使連接的電路斷開起到保險元件的作用，可有效地對電路中的重要元件進行保護。

熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)的(de)(de)(de)種類很多(duo)，按工作方(fang)式(shi)的(de)(de)(de)不(bu)(bu)(bu)同熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)可(ke)分為不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)和(he)可(ke)復(fu)(fu)式(shi)兩種。不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)在(zai)熔(rong)(rong)斷(duan)(duan)后是不(bu)(bu)(bu)能修復(fu)(fu)的(de)(de)(de)，只能更換新品。不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)的(de)(de)(de)外(wai)形和(he)普(pu)通(tong)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)相似，它(ta)有(you)線繞(rao)(rao)型、碳膜(mo)型、金(jin)屬(shu)膜(mo)型、氧化膜(mo)型和(he)化學淀積膜(mo)型。當(dang)過載引起(qi)元(yuan)件(jian)淚(lei)度上升(sheng)并(bing)達到某一溫(wen)度時(shi)，涂有(you)熔(rong)(rong)斷(duan)(duan)材(cai)料的(de)(de)(de)導電(dian)(dian)膜(mo)層或(huo)繞(rao)(rao)組線臣就會自動熔(rong)(rong)斷(duan)(duan)使電(dian)(dian)路斷(duan)(duan)開。不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)的(de)(de)(de)功(gong)率一般(ban)為0.25 - 3W ，阻(zu)(zu)(zu)(zu)值在(zai)0.2Ω- 20kΩ之間，當(dang)超過額(e)定功(gong)率9 - 25 倍時(shi)，可(ke)在(zai)60s 內熔(rong)(rong)斷(duan)(duan)。不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)的(de)(de)(de)外(wai)表(biao)大(da)多(duo)為灰色，阻(zu)(zu)(zu)(zu)值及精(jing)度一般(ban)用色環表(biao)示，其(qi)額(e)定功(gong)率則由(you)電(dian)(dian)阻(zu)(zu)(zu)(zu)器(qi)(qi)的(de)(de)(de)外(wai)形尺(chi)寸確定。在(zai)電(dian)(dian)子設備(bei)中(zhong)，大(da)多(duo)數采(cai)用不(bu)(bu)(bu)可(ke)復(fu)(fu)式(shi)熔(rong)(rong)斷(duan)(duan)電(dian)(dian)阻(zu)(zu)(zu)(zu)。

可(ke)復(fu)式(shi)(shi)熔(rong)(rong)(rong)斷電(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)是將普通電(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)與低(di)熔(rong)(rong)(rong)點(dian)金屬串(chuan)接(jie)(jie)在一(yi)(yi)個密封的(de)外殼中而構成的(de)，其電(dian)(dian)(dian)阻(zu)(zu)(zu)體的(de)一(yi)(yi)端(duan)采用(yong)(yong)(yong)低(di)熔(rong)(rong)(rong)點(dian)焊(han)料(liao)焊(han)接(jie)(jie)一(yi)(yi)根彈性(xing)金屬片(pian)或金屬絲，一(yi)(yi)旦(dan)元件過載(zai)發熱(re)時，焊(han)點(dian)首先熔(rong)(rong)(rong)化，彈性(xing)金屬片(pian)或金屬絲便與電(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)斷開(kai)，切(qie)斷電(dian)(dian)(dian)路起保(bao)護作用(yong)(yong)(yong)。可(ke)復(fu)式(shi)(shi)熔(rong)(rong)(rong)斷電(dian)(dian)(dian)阻(zu)(zu)(zu)絲在發生熔(rong)(rong)(rong)斷后，可(ke)以修(xiu)復(fu)使用(yong)(yong)(yong)。可(ke)復(fu)式(shi)(shi)熔(rong)(rong)(rong)斷電(dian)(dian)(dian)阻(zu)(zu)(zu)器(qi)(qi)(qi)的(de)功(gong)率(lv)一(yi)(yi)般為(wei)3 - 12W ，阻(zu)(zu)(zu)值在1Ω-5.1kΩ之(zhi)間(jian)，熔(rong)(rong)(rong)斷時間(jian)在幾十秒至(zhi)幾百秒之(zhi)間(jian)。

文章源自：熔斷電阻器，旺詮合金電阻、旺詮(quan)合金電阻代理商