Digital Domestic Meter for the Measurement and Billing of Electricity in Mexico

摘要

This article describes the design, construction and characterization of a digital meter of electric energy based on a microcontroller. The meter carries out the calculation of the demand for the kWh consumption, being based on a staggered rate of domestic type of the Federal Commission of Electricity (C.F.E.) in Mexico. The prototype also presents voltage, current, power and time measurements. The instrument takes voltage and current samples of sinusoidal waves which are converted to digital in real time. The system is based on the microcontroller PIC16F874 of the Microchip technology. All the measured and calculated parameters are visualized in a screen of liquid glass of 2 X 16 characters. There is a menu where the parameters are selected to be shown. As a protection, when the electric power supply fails, the meter stores the energy consumption and the remaining parameters in a EEPROM memory. The prototype was divided in four stages: data acquisition, signal conditioning, signal processing and visualization of results, and together, they are a prototype of a digital meter of electric energy for C.F.E. At the end, a set of tests is presented for its characterization.