The Powerwalker VFD (Voltage and Frequency Dependent/Spannungs- and frequency dependent) series provides the simplest and most cost-effective option your equipment from power surges and blackouts to protect. The input voltage deviates by more than 10% of the adjusted typical input voltage from the UPS switches to battery mode and supplies connected equipment with generated electricity from the battery. If the input voltage falls within normal range, the UPS switches back to mains operation. In the event of a total failure of the power grid to supply the UPS is capable of using the generated alternating current from the battery to the connected equipment for several more minutes with power. The duration of supply is dependent on the model and the current consumption of the connected consumer.