380伏(fu)(fu)(fu)三(san)相(xiang)(xiang)(xiang)四線電(dian)(dian)路中,任意兩根(gen)火(huo)線之(zhi)間的電(dian)(dian)壓都是(shi)380伏(fu)(fu)(fu),任意一根(gen)火(huo)線與(yu)零線之(zhi)間都可以(yi)(yi)組成(cheng)220伏(fu)(fu)(fu)。這(zhe)個系統(tong)可以(yi)(yi)形成(cheng)三(san)種(zhong)電(dian)(dian)源:即單相(xiang)(xiang)(xiang)220伏(fu)(fu)(fu)電(dian)(dian)源,單相(xiang)(xiang)(xiang)380伏(fu)(fu)(fu)電(dian)(dian)源,三(san)相(xiang)(xiang)(xiang)380伏(fu)(fu)(fu)電(dian)(dian)源,第(di) I 種(zhong)家用比較多,第(di)三(san)種(zhong)工(gong)廠里電(dian)(dian)機類用得(de)多,第(di)二種(zhong)用得(de)少,只有交流電(dian)(dian)焊機經常用到單相(xiang)(xiang)(xiang)380伏(fu)(fu)(fu)電(dian)(dian)源。