Rabbit® Helps to Create a "Cool House"
OurCoolHouse.com Uses the RabbitCore® RCM3700 in Web Energy Logger
The Dynamic C complier provided easy access to many of the functions required by my application, including multi-tasking, serial interfaces, Ethernet stack and web service.
—Phil Malone, OurCoolHouse.com
Today’s modern HVAC systems are more efficient than their predecessors, enabling users to maintain the right temperatures for green living spaces. If usage is not monitored, however, energy is wasted. Even efficient alternatives for heating and ventilation, such as solar and geothermal systems, present the problem of gauging true energy savings and maximum efficiency of the environmental system. Current systems rely on temperature based sensors to indicate when a preset threshold has been reached, triggering the system to either turn on or off. Phil Malone of OurCoolHouse.com developed the Web Energy Logger (WEL), featuring the RabbitCore RCM3700, to provide customers a global view of their environments so they can fine-tune energy consumption for optimal efficiency.
The WEL provides tools that allow users to implement an affordable yet highly sophisticated environmental monitoring system. This Internet appliance is designed to monitor a 1-Wire sensor network. At the heart of the WEL is the Ethernet enabled RabbitCore RCM3700 module. Depending on the application, the user can connect and monitor temperature sensors and other interfaces such as HVAC equipment.
A typical installation includes numerous temperature and input sensors covering different environmental zones throughout the home. The sensors are connected to a 1-Wire network feeding back to the WEL. The 1-Wire network connects to the 1-Wire interface, which then connects to the RCM3700. A watt-meter interface device monitors the facility load and utility room load. Other inputs run into a local run monitor that senses when external equipment is switched on or off, sending data to the RCM3700 via contact-closure sensor inputs. Sensors are polled every six seconds, offering a near real-time glimpse of the environmental data. The data is then scaled and filtered since each sensor and input has different measurement settings, helping to keep the data consistent for proper analysis.
Since the RCM3700 is also a web server for configuration, users may assign values to each sensor via a web interface. Data points are time stamped by a real-time clock and sent to the HTTP web server or to a local PC via an RS-232 serial interface.
Malone explains, “I needed a compact datalogger that could handle lots of thermal inputs without the expense of many dedicated input channels.”
Malone started his development with a PC based system using a 1-Wire network, but found this solution to be unreliable. He decided to transition to an embedded solution and found Rabbit through a wide market search. Rabbit provided a solution that enabled Malone to use an off-the-shelf product for the proof-of-concept, and also supported Ethernet for an Internet appliance style application and web server code for browser based configuration.
“The RCM3700 was extremely economical and provided easy connection through the standard 0.1 inch pin spacer header,” says Malone.
The RCM3700 offered the right features at the right price and could be designed without surface mount components. Rabbit’s Dynamic C® integrated development environment also provided an incredible value to the WEL.
“The Dynamic C complier provided easy access to many of the functions required by my application, including multi-tasking, serial interfaces, Ethernet stack and web service. As my application grew, additional functions were easy to add and schedule within the timing constraints put on the logging system,” explains Malone.
The RCM3700 hardware and Dynamic C software enabled OurCoolHouse.com to quickly develop a low-cost, low-power solution that enables users to fine-tune their HVAC systems to work at optimal efficiency, maintaining a green living environment.
For more information on the Web Energy Logger (WEL), visit: www.welserver.com
Submit your design application
success story to press@rabbit.com
Read more Customer Success Stories
