unsuitable as an inverter

After an initial exchange by service Eaton, the product still does not work properly, the battery will not take over during cuts. According to them, there would be a food sensitivity problem that my PC would not support 10ms required for the battery to take over. Perhaps they should state this in the product features: adapted to the PC very sensitive and capable of operating on their own until the battery decides to take over !. And of course, to achieve this balance, it took over a month and I can not even return the product !!!!!!