170 likes | 350 Views
Home Energy Monitor. Yolanda Haynes DeLean Tolbert Advisor: J. Miller. Project Overview. Wireless Watt hour meter Displays various energy measurements Remotely control the state of an appliance. Problem Statement.
E N D
Home Energy Monitor Yolanda Haynes DeLean Tolbert Advisor: J. Miller
Project Overview • Wireless Watt hour meter • Displays various energy measurements • Remotely control the state of an appliance
Problem Statement The main goal of the design is to allow consumers to measure and control the amount of energy consumed by a specific household appliance.
Specifications Electrical: • Operating Voltage/Maximum Input Voltage: 115 VAC • Maximum Input Current: up to 30 Amps (A) • High current isolation via linear optoisolation IC’s • Accuracy 0.1% error in active energy measurement Wireless: • Range: 100 feet • Protocol: Radio Frequency - Xbee • Frequency: 2.4 GHz
Specifications (cont.) • Environmental: • Operating Temperature: 0 - 50ºC • Operating Environment: Indoors • Software: • User Interfaces: Website • Secure login
Design Choices • LCD vs. LED • Relay vs. X10 • Xbee vs. Other RF • Energy IC vs. circuitry • CT vs. Shunt • Voltage Divider vs. VT
Subsystems Website Other system: Web interface
PIC16F917 • The Brains/Core • Function • Manipulate • Display • Store • SPI Interface • ADE7753 Energy IC • Shares the oscillator • Controls • push buttons, relay • 40 pins • IC, Xbee, LCD interface
Current and Voltage Sensing Low power consumption Proportional reduced current 1001:1 voltage divider • Current transformers (CT) provides isolation • Safer
Energy IC • Performs power related calculations: • Irms; VA; VAR; Vrms; Watt • Measures energy • Analog voltage/current inputs • Reduces circuit complexity • 800 Hz sampling frequency • Measurements every 0.001 seconds • Communicates with PIC
5 V Power Supply • PIC and Energy IC require 5V DC • Simple Design • Materials • 9 volt Alkaline battery • Voltage regulators • L7805- 5 V regulator • Output 5V DC • Maximum Input: 35 V DC
PIC16F917 Relay Relay +5 V • Appliance control • On/off • Pull-up resistor • Higher current • Transistor • Saturation • Protection diode • High voltage 1N4007 Resistor
Xbee Xbee Wireless IEEE 802.15.4 Personal Area Network Coordinator Remote node Serial communication UART Zigbee Same technology as Xbee Being use for advance metering Tx RX Dout Din 2 25 3 Xbee PIC16F917
User interfaces • LCD • Basic 16x2 • 4-bit mode • HD4478 chipset • Website • Remote access • Secure • ASP.net Website Flow chart
Acknowledgements • Advisor- Professor John Miller • Electronics Technician-Jesse Cross • Electrical Engineer, Harman International- David Haff • Network Engineer, Verizon Wireless- David Kuhn • Fall ’09 Senior Design students
234 Conclusion This system allows the user to monitor energy consumption and control the on/off state of an appliance remotely. This system is convenient and easy to use. In this applications a inexpensive, secure and safe control system has been presented.