The circuit shown is a microcontroller based Energy Meter that uses MCP3905A as its main component, which is an energy-metering ICs that supplies average power information through a pulse with direct drive for mechanical counter. It includes a higher-frequency output supplying instantaneous power information for calibration while conforming the IEC 62053 International Metering Standard Specification. The energy meter provides exceptional accuracy in measuring the amount of energy consumed by an electrically powered device. It can significantly read immediate power usage, which may be used to perceive future energy consumption.
Microchip’s MCP3905A energy meter reference design is a standalone, single-phase residential meter for active energy meter design. In addition, MCP3906A can be used in the project. For calibrating the frequency output, a voltage divider calibration circuit was optimized. Each meter must be calibrated using the voltage divider circuit going into Channel 1 of the MCP3905A/06A. The MCP3905A/06A has appropriate bypass capacitors on VDD coming from the DC power supply circuitry and has its input logic pins connected to user-selectable jumpers, with the exception of the HPF pin. For this system, the HPF is turned ON with this pin connected to VDD. Moreover, the DC power supply is created from a half-wave Zener diode limited AC signal feeding a 7805 +5V regulator. The Zener diode D2 however, limits the peak voltage to 15V while the optical isolator is included in the reference design as an additional level of protection for other circuitry.
Energy meter system had been widely used to measure the energy consumption to residents, industries and businesses benefiting the power usage. It is typically calibrated in billing units such as kilowatt-hour and periodic readings of electric meters, which establishes billing cycles and energy used.
For more detail: Energy Meter based on MCU