Electronic watt hour meter designed specially to confirm the data measured during power failure

摘要

Disclosed is an electronic watt hour meter having a function of checking weighing data during a power failure. The present invention provides a power supply transformer in which an AC voltage drop is applied, a power supply circuit for converting to a DC power supply, and a power failure compensation that operates as an auxiliary power supply for supplying power necessary for maintaining measurement-related data of the instrument, time counting, and display during power failure. A power circuit unit comprising a portion; A power / frequency conversion unit comprising a voltage signal conversion unit, a current signal conversion unit, a multiplier for receiving and multiplying signals corresponding to respective voltages and currents output, and a frequency converter for converting the multiplied signals to a corresponding frequency ; An oscillation circuit, an EEPROM for storing weighing data, an operation switch for generating an operation signal, an external control signal output unit for outputting a drive signal to the outside, a power monitoring circuit for transmitting an electrostatic signal in case of power failure, and the positive signal And a CPU for outputting a display signal for displaying weighing related data in combination with an operation signal; And a display unit which displays the weighing related data by the display signal. According to the present invention, not only has a time and weighing maintenance function inside the meter, but also has a merit that can check the weighing value at the time of the meter reading by adding a function to check the same.