The PowerWalker VFD (Voltage and Frequency Dependent) series offers the easiest and most cost-effective way to protect your devices from power fluctuations and power outages. If the input voltage deviates by more than 10% from the set typical input voltage, the UPS switches to battery mode and supplies the connected devices with power generated from the battery. If the input voltage is back in the normal range, the UPS switches back to mains operation. In the event of a total power failure, the UPS is able to continue to supply the connected devices with power for several minutes using the alternating current generated from the battery. The duration of the supply depends on the model used and the power consumption of the connected consumers.