Single Phase E-Meter for Low Cost and Power Needs based on PIC18F87J72:
Here is a smart single-phase meter reference design that meets the cost and power requirements of a single-phase system. To cut down cost, the design uses a shunt for the current sensor in place of expensive current transformers. The design uses a PIC18F87J72 MCU with Analog Front End to drive the LCD and calculate the parameters like active/ reactive powers, RMS currents and voltages, forward/reverse energies, and more. To meet accuracy requirements, a Microchip’s energy meter software is provided to quickly calibrate and monitor the meter with the help of MCU. Click here to download the reference design.
Low-cost Single-Phase E-Meter with Tamper Detection:
This is a simple and low-cost single-phase meter reference design that calculates active and reactive energy in both phase and neutral channels using a 32-bit MCU. A shunt resistor is used as a transducer for phase current sensing and a current transformer is used for neutral current sensing. The design includes tamper detection and can detect neutral missing with a current transformer and can log power-failure event with a built-in RTC. The Kinetis 32-bit ARM MCU with AFEs implements Discrete Fourier transformation (DFT) for accurate measurements. Click here to know more about the reference design.
Single-Phase E-Meter for Residential Metering with I2C:
The following reference design is a cost-optimised, high-performance single-phase meter for residential metering with two wire installations. It can be used in smart-grid applications by connecting to Zigbee network using the I2C interface. The design features a Kinetis MK30X256 ARM MCU for active and reactive power measurements that are displayed on a built-in LCD. The design includes cost-effective voltage sensing using an inexpensive resistor divider. The system can switch to low-power mode with the help of an in-built RTC operated by a 3V battery. The BOM of the system is kept low.Click here for detailed reference design.