The 500kVA inverter has two modes,

Basically, DC 630~900V, AC range is 360~440V, namely 400V.

Because the DC voltage must be always higher than the rectifying voltage in a inverter, 440*1.414=622V. But in some cases, the battery is lower than 630V, say 600V, the AC voltage tolerance became 600/1.414=424V, to make the nominal voltage just in the middle of lower limit and higher limit, we added a mode as 380V, for the batteries in DC 600~900V.

ANSI voltage limit on 480V is 508V, 508/480=1.058, while 424/400=1.06, so I believe using a 400V:480V transformer even when the inverter is set to 380V is also good.