Abstract: A metering system includes an electronic register having a non-volatile storage into which data is written upon the detection of a power outage. A power supply and monitor provides a regulated voltage for the electronic register and contains a capacitor which normally stores a sufficient quantity of electric energy to continue operation of the electronic register for a long enough period of time to complete the writing of data to the non-volatile storage. The discharge rate of the capacitor is linearly controlled to sustain the regulated voltage at its normal regulated value for the required period of time. An electronic meter is shut down upon the detection of a power outage to remove a portion of the load on the power supply to aid in sustaining the regulated voltage for the required period of time. The detection of momentary power outages is prevented by forcing the capacitor to charge to a prescribed voltage level before a subsequent outage can be detected.