1) There is only one AC port marked 4000W/220-240 (or 6000W/220-240) on the Split Phase Fusion Boxes that can power the High-voltage devices. Other 6 AC ports cannot load more than 2000W on EP500 (3000W on EP500Pro).
2) Under Split Phase Bonding mode, the total load power of all AC ports (on the machine and Split Phase Fusion Boxes) can not exceed 4000W for EP500 (6000W for EP500Pro)