當市電(dian)(dian)(dian)(dian)供電(dian)(dian)(dian)(dian)中斷或市電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓(ya)超限 (±15%或±20%額定輸入電(dian)(dian)(dian)(dian)壓(ya))時(shi),互投裝(zhuang)置將立(li)即投切(qie)至逆變器供電(dian)(dian)(dian)(dian),在電(dian)(dian)(dian)(dian)池組所提供的(de)(de)直流能源的(de)(de)支持(chi)下,此時(shi),用戶(hu)負載所使用的(de)(de)電(dian)(dian)(dian)(dian)源是(shi)通(tong)過(guo)EPS的(de)(de)逆變器轉換的(de)(de)交(jiao)流電(dian)(dian)(dian)(dian)源,而不是(shi)來自(zi)市電(dian)(dian)(dian)(dian)