The Wattcher

A General Purpose Sensor Network with Emphasis on Power Monitoring

The purpose of this project, the Wattcher, is to design and build a Zigbee based utility monitoring and control system. The resulting system may be used for any utility monitoring, such as water or gas, but focuses on electric power consumption at a standard American 120V wall outlet. The system’s network is a scalable star topology featuring self-powered Power Measuring (PM) nodes and a base-station. PM nodes are capable of storing sampled data, which are time stamped via a real-time clock (RTC). Each PM node also consists of external LEDs displaying the current status of the node. The base-station automatically checks and polls PM nodes for their status and whether or not they have any stored data. The software application at the base-station stores the received data from individual PM nodes in a text file, which can then be plotted on a user friendly graphical interface. The GUI allows the user to modify the data sampling rate of the PM node. The user can also specify which sensor peripherals on each PM node are actively collecting data. A key feature of the Wattcher is that the system is not limited to measuring utilities and it can easily be modified to a general purpose sensor network for various applications.