一、熔斷器是什么東西
熔(rong)(rong)斷(duan)器(qi)(qi)是一種電(dian)(dian)(dian)(dian)(dian)路的安全保(bao)護裝置(zhi),當電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)超過規定值時,通過本身發熱使熔(rong)(rong)體熔(rong)(rong)斷(duan),從而斷(duan)開(kai)電(dian)(dian)(dian)(dian)(dian)路,廣泛應用(yong)(yong)于高低壓配(pei)電(dian)(dian)(dian)(dian)(dian)系統和控制系統以及用(yong)(yong)電(dian)(dian)(dian)(dian)(dian)設備中,作(zuo)為短路和過電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的保(bao)護器(qi)(qi),是應用(yong)(yong)比較普遍的保(bao)護器(qi)(qi)件之一。
二、熔斷器有哪幾種類型
熔(rong)斷(duan)器的種類眾多(duo),按使用電(dian)壓可分為(wei)高壓熔(rong)斷(duan)器和(he)低壓熔(rong)斷(duan)器,按結構可分為(wei)敞開式(shi)、半封閉式(shi)、管式(shi)和(he)噴射式(shi)熔(rong)斷(duan)器,其中比較常用熔(rong)斷(duan)器有:
1、插入式熔斷器
常用于380V及以(yi)下(xia)電(dian)壓等級的線路末端,作(zuo)為(wei)配電(dian)支線或電(dian)氣設備的短路保護(hu)用。
2、螺旋式熔斷器
熔(rong)體(ti)上(shang)的上(shang)端蓋有(you)一熔(rong)斷(duan)指示器,一旦熔(rong)體(ti)熔(rong)斷(duan),指示器馬上(shang)彈出,可通過瓷帽上(shang)的玻璃孔觀(guan)察到,一般多用于電壓等級(ji)500V及其以下(xia)、電流等級(ji)200A以下(xia)的電路中,作短(duan)路保護。
3、封閉式熔斷器
可分(fen)為有填(tian)料(liao)熔(rong)(rong)斷(duan)(duan)器(qi)和(he)無(wu)填(tian)料(liao)熔(rong)(rong)斷(duan)(duan)器(qi)兩種(zhong),有填(tian)料(liao)熔(rong)(rong)斷(duan)(duan)器(qi)一般用方形瓷(ci)管,內裝石(shi)英砂及熔(rong)(rong)體,分(fen)斷(duan)(duan)能力(li)強(qiang),用于電(dian)(dian)壓等(deng)級500V以(yi)下、電(dian)(dian)流等(deng)級1KA以(yi)下的電(dian)(dian)路中;無(wu)填(tian)料(liao)密(mi)閉(bi)式熔(rong)(rong)斷(duan)(duan)器(qi)將熔(rong)(rong)體裝入密(mi)閉(bi)式圓筒(tong)中,分(fen)斷(duan)(duan)能力(li)稍(shao)小(xiao),用于500V以(yi)下,600A以(yi)下電(dian)(dian)力(li)網或配電(dian)(dian)設備中。
4、快速熔斷器
主要用于半(ban)導(dao)體(ti)整流(liu)元件或(huo)整流(liu)裝置的短路保護,因為半(ban)導(dao)體(ti)元件的過載(zai)能(neng)力(li)很(hen)低,因此(ci)需(xu)要短路時有快速(su)熔(rong)斷的能(neng)力(li),熔(rong)體(ti)材(cai)料和形狀(zhuang)是銀(yin)片沖制的有V形深槽的變截面熔(rong)體(ti)。
5、自復熔斷器
以金屬(shu)鈉(na)作熔(rong)體,當電(dian)(dian)路(lu)發(fa)生短路(lu)故障時,短路(lu)電(dian)(dian)流產生高溫使(shi)鈉(na)迅速汽(qi)化(hua),汽(qi)態鈉(na)呈現高阻態,從而(er)限制了短路(lu)電(dian)(dian)流;當短路(lu)電(dian)(dian)流消失(shi)后,溫度下降,金屬(shu)鈉(na)又可(ke)以恢復原來的良好導電(dian)(dian)性能(neng)。
三、熔斷器的優缺點
1、熔斷器的優點
價格便宜,體積小,短(duan)路(lu)分斷能力(li)較強,電路(lu)發生過載短(duan)路(lu)時,采用熔斷器切斷短(duan)路(lu)更為(wei)安(an)全。
2、熔斷器的缺點
熔(rong)斷(duan)器屬(shu)于一次性(xing)易(yi)耗件,過(guo)載、短路保(bao)護熔(rong)斷(duan)后,需更換熔(rong)芯,且功能相對比(bi)較(jiao)單一。