SGS Weather Station

Please visit the SGS Weather Station website at weather.hexoc.com.

The weather station project started life as a standalone battery powered datalogging system. It was built for a school project, taking around three months to design and build. Everything was built from scratch, the casings and sensors were either vacuum formed or CAD/CAM milled from HIPS.

The electronics was microcontroller based (PICAXE 18X originally) and used a DS1307 to log data to EEPROM once every fifteen minutes.

After the school project finished work on the station continued until it became what it is today. The system now updates to the internet every fifteen minutes. The PICAXE sends a serial string to a Lantronix XPORT that calls a PHP script on this server (hexoc.com). The PHP page's query string contains all the variables from the sensors. PHP and MySQL systems then kick in to adjust ADC reads and other such things, before data is stored in the database. One month of data is stored there, after which data is archived to CSV files by cron.

The station now runs a PICAXE 28X1 which allows hardware based serial IO. The clock has been upgraded to a more accurate model (DS3231). The PCB is currently on its second revision. The XPORT draws a relatively large amount of current, so the PICAXE can switch it on and off when required. The XPORT and power electronics (eg. regulators) sit in a nearby greenhouse, connected to the station via a 5m lead. A 50m ethernet patch lead runs under the floor to connect the XPORT to the school network.

Work is still ongoing with this project although most things are now largely complete. Please see the issues page here for current station issues that are waiting to be fixed.

Built by Matthew Brejza, Jon Sowman and Ben Oxley between 2007-9.