B級浪(lang)(lang)涌保(bao)護器主要用(yong)于防雷保(bao)護等電(dian)(dian)位連接(jie)。B級浪(lang)(lang)涌保(bao)護器在電(dian)(dian)源(yuan)系(xi)統中的(de)(de)(de)應用(yong)和(he)熔斷電(dian)(dian)阻需要合理搭配(pei)，考慮到它們首先要承(cheng)載電(dian)(dian)源(yuan)短路電(dian)(dian)流，與(yu)電(dian)(dian)源(yuan)續流相比，雷電(dian)(dian)浪(lang)(lang)涌電(dian)(dian)流在配(pei)電(dian)(dian)系(xi)統中是不(bu)可避免(mian)的(de)(de)(de)。今天，鈞和(he)電(dian)(dian)子為您詳細講述B級浪(lang)(lang)涌保(bao)護器與(yu)熔斷器的(de)(de)(de)搭配(pei)應用(yong)。

一、熔斷電阻的(de)三種特(te)性

1.不(bu)融化

雷(lei)電(dian)浪涌電(dian)流輸入(ru)的能量太低不足以使熔斷(duan)電(dian)阻熔化(hua)。

2.熔化

雷(lei)電(dian)(dian)(dian)(dian)(dian)浪(lang)涌電(dian)(dian)(dian)(dian)(dian)流的(de)能量足夠熔化熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)，并因此中斷了通(tong)過(guo)的(de)電(dian)(dian)(dian)(dian)(dian)流通(tong)路。典型的(de)熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)性能是外加(jia)的(de)雷(lei)電(dian)(dian)(dian)(dian)(dian)浪(lang)涌電(dian)(dian)(dian)(dian)(dian)流可以(yi)通(tong)過(guo)而(er)不(bu)受熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)性能的(de)影(ying)響。當雷(lei)電(dian)(dian)(dian)(dian)(dian)浪(lang)涌電(dian)(dian)(dian)(dian)(dian)流超過(guo)熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)的(de)熔化點以(yi)后，在(zai)熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)中產生電(dian)(dian)(dian)(dian)(dian)弧，體現為熔斷電(dian)(dian)(dian)(dian)(dian)阻(zu)上的(de)電(dian)(dian)(dian)(dian)(dian)位差。

3.爆炸

雷電浪涌電流的瞬時能量(liang)夠大，以至于熔斷(duan)電阻在(zai)爆炸中蒸發，結(jie)果(guo)是熔斷(duan)電阻的外殼可能破裂。

二、浪涌(yong)保護(hu)器與(yu)熔斷器的搭配注意事項

（一(yi)）熔(rong)斷(duan)器(qi)應能將失(shi)效的浪涌(yong)保(bao)護器(qi)從低壓(ya)系統中切除

在浪(lang)涌(yong)保護(hu)(hu)(hu)器(qi)與(yu)熔(rong)(rong)斷(duan)電(dian)阻的(de)應用問題(ti)(ti)上，不(bu)同(tong)的(de)問題(ti)(ti)需要(yao)不(bu)同(tong)的(de)浪(lang)涌(yong)保護(hu)(hu)(hu)器(qi)后備熔(rong)(rong)斷(duan)電(dian)阻。當浪(lang)涌(yong)保護(hu)(hu)(hu)器(qi)失(shi)效(xiao)時(shi)，熔(rong)(rong)斷(duan)電(dian)阻提供(gong)間接接觸防護(hu)(hu)(hu)，這是所有B級(ji)、C級(ji)和(he)D級(ji)浪(lang)涌(yong)保護(hu)(hu)(hu)器(qi)的(de)后備熔(rong)(rong)斷(duan)電(dian)阻的(de)任務，因此熔(rong)(rong)斷(duan)電(dian)阻必須設計成能將(jiang)失(shi)效(xiao)浪(lang)涌(yong)保護(hu)(hu)(hu)器(qi)在要(yao)求(qiu)的(de)時(shi)間內安全(quan)地(di)從(cong)低壓系(xi)統中切除。

（二）浪涌保護器后備熔斷(duan)電(dian)阻必(bi)須盡可(ke)能大(da)

為了保證(zheng)浪(lang)涌(yong)保護(hu)器(qi)(qi)的(de)短路承受能(neng)力，在(zai)(zai)任何情況下都不得超過允許的(de)最(zui)(zui)大后(hou)備(bei)熔(rong)斷電(dian)阻(zu)承載能(neng)力。基于火花間(jian)隙的(de)浪(lang)涌(yong)保護(hu)器(qi)(qi)，可能(neng)出現電(dian)源(yuan)續流，在(zai)(zai)應(ying)用最(zui)(zui)大允許后(hou)備(bei)熔(rong)斷電(dian)阻(zu)時，也會達(da)到浪(lang)涌(yong)保護(hu)器(qi)(qi)的(de)最(zui)(zui)大續流熄滅(mie)容量。如(ru)果后(hou)備(bei)熔(rong)斷電(dian)阻(zu)較(jiao)小，可能(neng)會切斷本可以由(you)浪(lang)涌(yong)保護(hu)器(qi)(qi)本身安全熄滅(mie)的(de)電(dian)源(yuan)續流。因此，浪(lang)涌(yong)保護(hu)器(qi)(qi)后(hou)備(bei)熔(rong)斷電(dian)阻(zu)必(bi)須盡可能(neng)大。如(ru)果條件(jian)允許，應(ying)當避(bi)(bi)免裝(zhuang)設避(bi)(bi)雷器(qi)(qi)支路上的(de)獨立后(hou)備(bei)熔(rong)斷電(dian)阻(zu)。

（三）采用帶(dai)有(you)吹(chui)弧技術(shu)的浪涌保(bao)護(hu)器(qi)

為(wei)了(le)克服上(shang)(shang)述浪涌保護器與熔(rong)斷(duan)(duan)(duan)電(dian)(dian)阻(zu)之(zhi)間(jian)的配(pei)合問題，一種采用吹(chui)弧(hu)技(ji)(ji)術(shu)得到了(le)應用。該浪涌保護器火(huo)花間(jian)隙電(dian)(dian)弧(hu)電(dian)(dian)壓在(zai)幅值上(shang)(shang)幾乎等于系(xi)(xi)統電(dian)(dian)壓，不(bu)會出現普通(tong)火(huo)花間(jian)隙典(dian)型的系(xi)(xi)統電(dian)(dian)壓降，避免了(le)對電(dian)(dian)壓降或(huo)(huo)供電(dian)(dian)電(dian)(dian)壓偏移敏感的電(dian)(dian)子設備的干擾。電(dian)(dian)源續流限制的效果明顯(xian)。即使在(zai)36kA的沖擊(ji)短路(lu)電(dian)(dian)流下(xia)，通(tong)過被測試的采用吹(chui)弧(hu)技(ji)(ji)術(shu)的浪涌保護器的弧(hu)前(qian)電(dian)(dian)流也只有1.6kA。在(zai)主電(dian)(dian)源系(xi)(xi)統中應用具有吹(chui)弧(hu)技(ji)(ji)術(shu)的B級浪涌保護器，可(ke)以避免在(zai)供電(dian)(dian)入口端(duan)或(huo)(huo)表盤上(shang)(shang)的后備熔(rong)斷(duan)(duan)(duan)電(dian)(dian)阻(zu)被電(dian)(dian)源續流熔(rong)斷(duan)(duan)(duan)。