Ryan Herbst

Weather & Environmental Monitor

Weather Station Block Diagram

My weather station consist of a number of Oregon Scientific sensor units which broadcast data in the ~433Mhz frequency band. I acquired the core units when I purchased a WMR918 weather station. For a while I had interfaced the WMR918 base station to my PC to collect and record weather information. Last year I found out about the RFXCOM series of transmitters and receivers which are used for home automation. The advantage of the RXFCOM receier is that it does not have a limit on the number of sender units from which data can be collected. When I converted to the RFXCOM receiver I was able to add a pool temperature sensor and read information from the temperature sensor in my camper. I plan to add a number of additional sensors in the future.

I currently have the following climate sensors in my home automation setup:

  • Anemometer – WGR968 from Oregon Scientific. (Wind speed and direction)
  • Outdoor Sensor – THGR918 from Oregon Scientific. (Temperature and humidity)
  • Indoor Sensor – BTHR918N from Oregon Scientific. (Temperature, humidity & barometric pressure)
  • Garage Sensor – THGN122N from Oregon Scientific. (Temperature and humidity)
  • Kids Bedroom Sensor – THGN122N from Oregon Scientific. (Temperature and humidity)
  • Master Bedroom Sensor – THGN122N from Oregon Scientific. (Temperature and humidity)
  • Rain Gauge – THN132N from Oregon Scientific. (Running rainfall count and rainfall rate)
  • Pool Sensor – THWR800 from Oregon Scientific. (Floating water proof temperature sensor)
  • Campre Sensor – THN132N from Oregon Scientific (Temperature)

The camper sensor came as a wireless sender/receiver pair that I use to measure indoor and outdoor temperature when camping. When the camper is parked I move the outdoor sensor into the camper and use it to measure the inside camper temperature while it is parked in my front yard.

The floating pool sensor is used to control my pool heater as well as monitor the pool temperature.

After I purchased the RFXCOM receiver I found the RFXCOM XPL gateway from www.iranger.com. This gateway converts all received RF messages into sensor.basic xPL messages. This software is distributed as a pre-compiled Linux binary.

Once weather data is broadcast on the xPL network it is received by my xPL_Mysql daemon and added to a MySql database. It is also received by my home monitor display in my living room. The xPL message can also be received by a number of other clients which can be used to make decisions based upon the current set of environmental values. One example of this is a script that turns on or off the heat lamp in my chicken coup when the outdoor temperature gets too low.

Every 10 minutes a python software script is run which uploads me current weather data to my station page on www.weatherunderground.com:

weather_underground.py

Email me if you have any questions.

 

 

 

Amaroq Weather Station

Beresford Ave, Redwood City, CA
temp: 49.8 F (9.9 C) (9.9)
humidity: 77%
wind: From the NNE at 1.3 MPH Gusting to 1.3 MPH
pressure: 30.03" (1016.8 mb)
station: KCAREDWO4
hardware: WMR918
updated:January 20, 10:27 AM PST
local forecast