Bluewalker PowerWalker VFI 2000C LCD - UPS - 1600 Watts - 2000 VA 9 Ah - RS-232, USB - 4 output sockets - PFC (10120178) The PowerWalker VFI (Voltage and Frequency Independent) series provides a clean, interference-free power supply at all times, thanks to its online (double conversion) technology. In the first step of the double conversion process, incoming alternating current is converted into direct current and stored. In the second step, the stored direct current is converted back into alternating current and made available for consumers. This process ensures complete separation between the power supply network, which may experience fluctuations, and the stable and clean consumer-side power network generated by the UPS. Another advantage of this technology is that in the event of a power failure, there are no switching times that could lead to failures or damage in critical consumers.