電線“超負(fu)(fu)荷“指電線所(suo)受負(fu)(fu)荷超出原有負(fu)(fu)荷。電線也有它的載電規定。電流通過(guo)電線會(hui)使(shi)電線發熱(re)，這本來是正(zheng)常現象。但如果(guo)超負(fu)(fu)荷使(shi)用，細(xi)電線通過(guo)大(da)電流，就容易引起火災。

超(chao)負(fu)荷用(yong)電(dian)(dian)(dian)(dian)的(de)危險：家(jia)用(yong)電(dian)(dian)(dian)(dian)線(xian)超(chao)負(fu)荷有危險。電(dian)(dian)(dian)(dian)線(xian)有它的(de)載電(dian)(dian)(dian)(dian)規定。電(dian)(dian)(dian)(dian)流(liu)通(tong)過電(dian)(dian)(dian)(dian)線(xian)會使(shi)電(dian)(dian)(dian)(dian)線(xian)發熱(re)，這本來是正常現象。但如果超(chao)負(fu)荷使(shi)用(yong)，細電(dian)(dian)(dian)(dian)線(xian)通(tong)過大(da)電(dian)(dian)(dian)(dian)流(liu)，就(jiu)容易引(yin)起火災。

家庭(ting)常用的電線(xian)(xian)一般用塑料線(xian)(xian)或橡膠絕(jue)緣線(xian)(xian)。選線(xian)(xian)時一定要注意(yi)電線(xian)(xian)的載流(liu)范(fan)圍，不同規格的電線(xian)(xian)有不同的載流(liu)范(fan)圍。室內安裝明線(xian)(xian)，環境溫度(du)不應高于35度。

在電(dian)(dian)線(xian)(xian)(xian)載流范圍(wei)內選用電(dian)(dian)線(xian)(xian)(xian)，電(dian)(dian)線(xian)(xian)(xian)不(bu)會(hui)(hui)發生過熱。但用電(dian)(dian)量(liang)超過電(dian)(dian)線(xian)(xian)(xian)的(de)載流范圍(wei)時，電(dian)(dian)線(xian)(xian)(xian)會(hui)(hui)發熱，電(dian)(dian)線(xian)(xian)(xian)的(de)發熱量(liang)和(he)電(dian)(dian)流強(qiang)度(du)的(de)平方成正比，如果電(dian)(dian)流強(qiang)度(du)增加2倍，發(fa)熱量就比原來(lai)增加4倍，會造成(cheng)電線過熱，容易(yi)引起(qi)火災。