絕緣(yuan)也(ye)要(yao)具有一定的機械(xie)物理性(xing)能(neng)(neng)和(he)加(jia)(jia)工(gong)制造的工(gong)藝性(xing)能(neng)(neng)。例如(ru)制造低壓電(dian)(dian)(dian)纜時(shi)(shi)，盡(jin)管從電(dian)(dian)(dian)氣性(xing)能(neng)(neng)方面(mian)考慮(lv)可以采(cai)用很薄的絕緣(yuan)，但從機械(xie)性(xing)能(neng)(neng)與加(jia)(jia)工(gong)工(gong)藝考慮(lv)，仍(reng)以稍厚一些為好(hao)，原(yuan)(yuan)因是絕緣(yuan)過薄，加(jia)(jia)工(gong)較困難(nan)，容(rong)易損(sun)壞。電(dian)(dian)(dian)力電(dian)(dian)(dian)纜主要(yao)考查導(dao)體(ti)的材質(zhi)和(he)截面(mian)積，若導(dao)體(ti)的材質(zhi)不(bu)好(hao)或截面(mian)積嚴重不(bu)足，就(jiu)會(hui)造成導(dao)體(ti)直流(liu)電(dian)(dian)(dian)阻(zu)嚴重超標，這種(zhong)電(dian)(dian)(dian)纜鋪設(she)在(zai)線(xian)路(lu)中就(jiu)會(hui)增加(jia)(jia)電(dian)(dian)(dian)流(liu)在(zai)線(xian)路(lu)上通過時(shi)(shi)的損(sun)耗。耐(nai)(nai)火(huo)電(dian)(dian)(dian)纜與阻(zu)燃(ran)(ran)(ran)電(dian)(dian)(dian)纜的原(yuan)(yuan)理不(bu)同：含鹵電(dian)(dian)(dian)纜阻(zu)燃(ran)(ran)(ran)原(yuan)(yuan)理是靠(kao)(kao)(kao)鹵素的阻(zu)燃(ran)(ran)(ran)效(xiao)應，無鹵電(dian)(dian)(dian)纜阻(zu)燃(ran)(ran)(ran)原(yuan)(yuan)理是靠(kao)(kao)(kao)析出(chu)水降低溫(wen)度來熄滅(mie)火(huo)焙；耐(nai)(nai)火(huo)電(dian)(dian)(dian)纜是靠(kao)(kao)(kao)耐(nai)(nai)火(huo)層中云(yun)母材料的耐(nai)(nai)火(huo)、耐(nai)(nai)熱的特性(xing)，保證(zheng)電(dian)(dian)(dian)纜在(zai)火(huo)災時(shi)(shi)也(ye)工(gong)作正(zheng)常。

耐(nai)火電(dian)(dian)(dian)纜(lan)與阻(zu)燃電(dian)(dian)(dian)纜(lan)的(de)原理(li)不(bu)同：含鹵(lu)(lu)電(dian)(dian)(dian)纜(lan)阻(zu)燃原理(li)是(shi)靠鹵(lu)(lu)素的(de)阻(zu)燃效應，無鹵(lu)(lu)電(dian)(dian)(dian)纜(lan)阻(zu)燃原理(li)是(shi)靠析出水降低溫度來熄(xi)滅火焙；耐(nai)火電(dian)(dian)(dian)纜(lan)是(shi)靠耐(nai)火層中云(yun)母材料(liao)的(de)耐(nai)火、耐(nai)熱的(de)特性，保證電(dian)(dian)(dian)纜(lan)在(zai)火災時(shi)也工作正常(chang)。絞合線芯可以采(cai)(cai)用非緊壓(ya)和(he)緊壓(ya)線芯兩種。交聯(lian)電(dian)(dian)(dian)纜(lan) 的(de)導電(dian)(dian)(dian)線芯通常(chang)采(cai)(cai)用絞合結構(gou)，1kV交聯(lian)電(dian)(dian)(dian)纜(lan)通常(chang)采(cai)(cai)用扇形(xing)、半(ban)圓形(xing)和(he)圓形(xing)。6kV以上交聯(lian)電(dian)(dian)(dian)纜(lan)采(cai)(cai)用圓形(xing)緊壓(ya)線芯。在(zai)導體(ti)上、絕緣層上、電(dian)(dian)(dian)纜(lan)芯上或(huo)電(dian)(dian)(dian)線電(dian)(dian)(dian)纜(lan)外(wai)層，為了防(fang)止外(wai)界(jie)電(dian)(dian)(dian)磁波干(gan)擾或(huo)是(shi)起均勻電(dian)(dian)(dian)埸作用，還包有(you)金屬帶、絲(si)或(huo)半(ban)導電(dian)(dian)(dian)塑料(liao)等(deng)材料(liao)。這些都稱為屏蔽層。

導體是(shi)指(zhi)能(neng)傳導電(dian)(dian)(dian)(dian)流的(de)物體，又稱為(wei)導電(dian)(dian)(dian)(dian)線芯。用(yong)作電(dian)(dian)(dian)(dian)線電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)導體的(de)材(cai)料(liao)，低壓電(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)型號，首先要有(you)(you)良好的(de)導電(dian)(dian)(dian)(dian)性能(neng)，即電(dian)(dian)(dian)(dian)阻要小(xiao)，以減少電(dian)(dian)(dian)(dian)流在線路(lu)上的(de)損耗(hao)。損耗(hao)與電(dian)(dian)(dian)(dian)流大小(xiao)、電(dian)(dian)(dian)(dian)阻大小(xiao)有(you)(you)直(zhi)接關系，并表現(xian)在導體的(de)發(fa)熱上。護(hu)層(ceng)是(shi)電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)外層(ceng)的(de)保護(hu)部分。根據電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)的(de)用(yong)途(tu)以及(ji)使用(yong)環境和(he)絕緣的(de)不同(tong)，護(hu)層(ceng)有(you)(you)許多(duo)不同(tong)型式(shi)和(he)結構(gou)，它們所(suo)起的(de)作用(yong)也(ye)不盡(jin)相(xiang)同(tong)。中高壓電(dian)(dian)(dian)(dian)纜(lan)(lan)(lan)一般(ban)采用(yong)過氧(yang)化物交(jiao)(jiao)聯(lian)(lian)，即用(yong)化學(xue)方(fang)法(fa)將線性分子通過化學(xue)交(jiao)(jiao)聯(lian)(lian)反應起來，轉化為(wei)立體網狀結構(gou)。化學(xue)交(jiao)(jiao)聯(lian)(lian)一般(ban)還可分為(wei)過氧(yang)化物交(jiao)(jiao)聯(lian)(lian)和(he)接枝(zhi)交(jiao)(jiao)聯(lian)(lian)兩(liang)種。