... hours (first time)2 minutes (operation)Electrical CharacteristicsPower supply 5VDC, Power adapter connected directly to 100VAC~220VAC. ... pollution)Backlight brightness Automatically adjust the brightness according to the environmentReal-time displayYear, month, day, week, clockTemperature, ... controller to control a ventilator, air cleaning device, or humidity device, based on the real-time measurements ...