Re: A data or application problem most likely
2) 480 volts. BS: There's no way that any UPS i've ever seen could operate or be wired so that could happen. The only possible thing that might have happened is that grid power was restored out of phase with the UPS inverter output, which could cause a big bang. However, UPS's are specifically designed to deal with that, with state change inhibited and the UPS phase adjusted until it's in sync with the grid input. No UPS could work without that logic.
UPS systems are usually either true online, or switched. With true online, the UPS inverter always supplies the load, with the grid input powering the inverter and float charging the batteries. With switched, the grid normally supplies the load directly and the batteries are idle, on float charge. For the latter, when the grid goes down, the inverter starts up from batteries to power the load, which is switched over from grid input, to UPS inverter, within a few cycles at most. All these things have smart microprocessor control, which continually samples mains quality and has lockout delays to ensure that brief transients don't cause an unnecessary switchover, Also, delays to ensure that grid power is clean and stable before re connecting to the load.
We've now had several stories abouty this, none of which seem real and ignoring the giant elephant in the room, which is that their disaster recover failed completely. The tech to do this has been around for decades, so how could it go so badly wrong, in a company of that stature ?...