CyberPower’s CP900AVR has a fairly easy-to-use interface with just two buttons (electricity on/off and mute) and 4 indicator lights (demonstrating in the event the device is turned on, once the battery backup kicks in, when AVR is activated, and when there’s a power overload) on the front with the device. https://andresikjhf.vidublog.com/35271827/battery-ups-fundamentals-explained