About the weather station

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Just how is the data presented on this website collected? A couple of pieces of equipment achieve this. 

Firstly the weather station itself. Originally manufactured by Dallas Semiconductors as an experimenters kit, it uses 1 wire chips, each with its own unique identity that enables many sensors to be found and addressed on the same wire. These chips digitize the weather conditions and return this information to a PC for interpretation by the software. Actually the term "1 Wire" is a bit of a misnomer as two wires are required for operation. 1 wire is the ground and the other supplies both power and receives the incoming data signal. 

Secondly the whole system is powered by a dedicated PC that uses software written by Arne Henricksen of Norway to receive and interpret the signals. A data sample is taken every second and a log is kept that records daily high lows. These logs can be opened in any spreadsheet application and analyzed, graphed etc. See some of the data collected from my station "HERE". A web page is also created and uploaded daily, making current weather conditions available to anyone with an internet connection, anywhere in the world. This page is viewable "HERE" 

Finally for the sensors themselves

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The main Weather Station Body. Constructed from UV resistant plastic it contains: 1 temp sensor Wind Direction Wind speed (anenometer)

The Rain Gauge. Same construction as the main body it contains a small "bucket" mechanism, that as it fills from the collection funnel is calibrated to "tip" at a resolution of 0.25mm. Each tip is recorded providing, rain rate, quantity and weekly monthly and yearly totals .

The Temperature Sensor. The actual sensor itself is tiny, being only a few millimeters in size.   The ds1820 temperature sensor. I have 5 temperature sensors located in various locations around our property. Inside the Main Body of the weather station and mounted on the roof. Inside the Office ("computer room"). Inside the Lounge Room. Outside, under the Verandah. (mounted in conjunction with the humidity sensor). Outside in a Stevenson Screen measuring the Air Temperature. This sensor is the one used for the daily statistics data. It is mounted in a ventilated Stevenson Screen ( see pictures to the left ) that gives the most accurate air temperature with protection from solar radiation.  The house is a great insulator from the outside elements, with the inside sensors recording an almost flat graph with very little temperature variation, while the outside sensors change with the prevailing conditions. It is usually a degree or so warmer under the verandah than the outside air temp. Buildings have a "microclimate" of their own.

The Humidity Sensor. The photo to the left shows the housing that contains both the humidity sensor and the ds1820 temp sensor labeled "Outside-Under Verandah. The two ends (coloured brown) are perforated with small holes that prevents the entry of any "wet" moisture, while still allowing good air flow over the contained sensors.

The Barometer. The latest addition to the stable, the barometer breaks from the 1 wire principles in that it needs an external power source.  Custom designed and built by David Bray and Jim Jennings especially for users of the 1 wire network. To see how well it tracks click on the picture below for a graph compared with Adelaide and Strathalbyn. Click for more detail

The system runs reliably 24 hours a day, 7 days a week, 365 days a year.