You can arrange a really low power and cost effective remote automated weather station by combining meteo sensors of your favourite brand with our ML-417AD(S)-PV LTE-m & NB-IoT data logger with integrated solar panel. The arranged AWS is very cost effective because all you need is our reasonably priced data logger and applicable meteo sensors of your choosing, you don’t need a big solar panel, big battery, charger or encapsulating cabinet.
Parameters monitored by an AWS
Common parameters monitored by an AWS are: Air temperature, humidity, barometric pressure, precipitation, wind speed and direction.
Temperature, humidity and barometric pressure
Air temperature, humidity and pressure are relatively slow rising and declining parameters and recording their instant values every 5 or 10 minutes is enough for weather monitoring that does not have to be in compliance with strict (governmental) regulations. To preserve power, the data logger will power the sensors during sampling only. The sensors of your choosing can be connected to the analog inputs or SDI-12 interface of the data logger.
Precipitation can be recorded by connecting a classical tipping bucket rain gauge to one of the digital inputs of the data logger. Counting bucket pulses draws negligible power from the data logger’s internal batteries. The data logger records rain intensity, quantity and cumulative quantity.
Wind speed and direction
Wind is a very fluctuating subject and an accurate impression can not be given by taking a sample once a while, it requires continues sampling. To maintain low power consumption you have to pick your wind sensors with care as you have to choose sensors that draw negligible power from the data logger’s internal batteries.
For wind speed you have to choose a classical powerless anemometer with magnet(s) and reed switch output, where each revolution of the anemometer causes one or multiple reed switch closures. The reed switch output can be connected to one of the digital inputs of the data logger. The data logger can sample the wind speed at 1Hz and record aggregated values (average, minimum, maximum, gust and standard deviation) every data log interval (e.g. 2 or 10 minutes).
Alternatively, you can use a powerless anemometer with an AC sine wave output (dynamo) and use a wave to pulse converter (ML-OC-W2P) in between the anemometer and a digital input of the data logger.
An example of such an anemometer is the: NRG 40C
For wind direction you have to choose a classical windvane with potentiometer output, which can be connected to the potentiometer input of the data logger. The data logger can sample the wind direction at 1Hz and record aggregated values (average, minimum, maximum and standard deviation) every data log interval (e.g. 2 or 10 minutes).
Note 1: The higher the potentiometer resistance, the lower the power consumption. To decrease consumption you could consider to add resistors in series with the potentiometer of the wind vane (one in the ground wire and an equal one in the excitation wire to the windvane). Adding a resistance equal to the wind vane’s potentiometer, will decrease the windvane’s consumption by 50%. Its preferred to have a total resistance of at least 3k Ohm.
Note 2: After connecting a wind vane with additional series resistors, its recommended to perform a 2 point user calibration (e.g. one point at 90° and one at 270°)
Here’s a useful document to download displaying the Davis D6410 configuration instructions.