當(dang)市(shi)電(dian)供(gong)電(dian)中斷或市(shi)電(dian)電(dian)壓(ya)超限 (±15%或±20%額定輸入電(dian)壓(ya))時(shi),互投裝(zhuang)置將立(li)即投切至逆(ni)變(bian)器(qi)供(gong)電(dian),在(zai)電(dian)池組所提供(gong)的直(zhi)流能(neng)源的支(zhi)持(chi)下,此時(shi),用(yong)戶負(fu)載所使(shi)用(yong)的電(dian)源是(shi)通過EPS的逆(ni)變(bian)器(qi)轉(zhuan)換的交流電(dian)源,而不是(shi)來(lai)自市(shi)電(dian)