Solar Project

This page launches the status window. The status window is refreshed every 300 seconds (typically half the update time).

This project periodically reads the temperature, checks the output of the solar panel then transmits the result in a small data packet. The receiver connects to the serial port on the PC. A small application listens to this port, when a good packet is received it updates the onscreen status, generates the simple result.html page and FTP's this to my home page.

The circuit was modified from an existing temperature monitoring project with a few additions and uses the same circuit board. The board contains a 433.92 MHz AM transmitter module, Atmel microcontroller and a Dallas Semiconductor DS1624 digital thermometer . In addition to this is a prototype board with rechargeable NiMH battery, discrete components for the charge circuit and a Real-Time-Clock IC and crystal (hidden behind top PCB). The Real-Time-Clock enables the processor to be put into a low power standby mode. The RTC will trigger the processor to wake up at a predefined interval and significantly reduces the power requirements. Due to the low operating power the solar panel in many respects is not required as it should run off battery for most the year. I had initially planed to have the processor running most the time in which the lifespan of the battery would of only been days or week(s). At some point I may add some more features.