Kindly note that the PM5350's RTC is backed-up by a capacitor (not a battery). So if the clock is set and auxiliary power supply to the meter remains cut-off for more than 30 seconds, next time auxiliary power is restored the RTC will reset to 00:00:00 hrs (date will reset to some value), and start running henceforth. Therefore, in event of Aux. power supply interruption, user must check and set RTC as required.