三相電加熱管

        380伏三相(xiang)四線電(dian)(dian)(dian)路中，任意(yi)兩根火線之(zhi)間的電(dian)(dian)(dian)壓(ya)都(dou)是380伏，任意(yi)一根火線與零線之(zhi)間都(dou)可以(yi)組(zu)成220伏。這個系統可以(yi)形成三種電(dian)(dian)(dian)源(yuan)(yuan)：即單相(xiang)220伏電(dian)(dian)(dian)源(yuan)(yuan)，單相(xiang)380伏電(dian)(dian)(dian)源(yuan)(yuan)，三相(xiang)380伏電(dian)(dian)(dian)源(yuan)(yuan)，第 I 種家用(yong)比較多(duo)(duo)，第三種工廠里(li)電(dian)(dian)(dian)機類用(yong)得(de)多(duo)(duo)，第二種用(yong)得(de)少，只有交流(liu)電(dian)(dian)(dian)焊機經(jing)常用(yong)到(dao)單相(xiang)380伏電(dian)(dian)(dian)源(yuan)(yuan)。