CyberPower’s CP900AVR has a fairly easy-to-use interface with just two buttons (electrical power on/off and mute) and 4 indicator lights (showing if the device is turned on, when the battery backup kicks in, when AVR is activated, and when there’s a power overload) over the front in the unit. Picture: https://kung-fu39379.blogvivi.com/36991120/the-best-side-of-smart-ups-1500-battery