Reading fan speed from the Barani MeteoShield Pro fan-aspirated model (FARS)

In this post, I explained how I use a Wemos D1 Mini microcontroller and a MOSFET module to control the fan speed of a wired fan-aspirated MeteoShield Pro from Barani Design. I am also testing a model with a fan powered by solar panels. Both come with two additional wires connected to a reed switch […]

Getting accurate NTC thermistor readings with a Wemos D1 Mini

A thermistor is a very common type of thermometer. They are cheap and readily available in many forms. Thermistors are are simple devices. A thermistor is basically nothing more than a resistor that changes its resistance with temperature. Very popular are 10K NTC thermistors. Negative Temperature Coefficient (NTC) means that resistance drops when temperature rises. […]

Using a 4-20 mA PT100 transmitter

In this post, I explained how I used an Adafruit MAX31865 clone in order to read a PT100 temperature sensor. Since then, I’ve tested an original Adafruit version as well. Accuracy from this board is a lot better. While I had to add a calibration offset of somewhere between 0.8 and 1.5 degrees to configurations using the […]

Reading a PT100 sensor with a Wemos D1 Mini

In my never ending quest for better temperature readings – or other ways of doing so, at least – I’ve begun trying other sensors than the SHT35. One of them is the PT100. It’s supposed to be very accurate. It it used in many different situations, from laboratory settings to industry. It’s also used in […]

Project Apogee part 2: power supply

Project Apogee requires me to rethink the power supply of my weather station. When I start writing this, the Meteodrenthe weather station runs on solar power only. The Davis components have their own panel inside the transmitters. Other custom elements use 2 watt 6 volt panels by Voltaic Systems. This has been an ideal solution […]

Project Apogee part 1: fan aspiration

My big project for the summer of 2021 is adding a fan aspirated radiation shield to my setup. My primary shield – the Barani MeteoShield Pro – is a superb product, but a passive shield it remains. It suffers from overheating in windless conditions. Those conditions do not occur too often at my location, but […]