As having someone in my family that suffers from type 2 diabetes, I made a small collection of insulin glass vial. I’ve tried to think about some uses for those vials and Voilà! I had the idea to use a vial as a waterproof casing for a digital temperature sensor.
The sensor I’ve used it’s the well known DS18B20. I bought few pieces some time ago, but I had a hard time thinking about what kind of casing to use with it in order to keep it clean and dry while measuring the temperature from outside. The answer to that problem is using the insulin glass vial.
In the next picture you can see the vial with the rubber piston extracted using a toothpick next to the DS18B20 sensor.
After that I’ve pulled the wires through the glass vial…
The next step was to solder the sensor to the wires… It’s actually simple to do that, but you have to use this schematic.
As you can see, the first and the third pin are soldered together because this is how you can use the sensor in parasitic mode. Those two pins are connected to GND. The second pin is used for power and data.
To keep the sensor at equal distance from the glass vial as it is possible to have condensed water vapors inside the vial, I’ve made some round spacers out of perforated prototyping board. The distance between spacers is kept using some heatshrinking tube on the white wire. The next picture shows the curing glue I’ve used to coat the spacers in order to keep the eventual moisture away from the exposed solder joints.
For fast curing of the glue I’ve used the hot air from my laptop cooling fan. 🙂
And this is how the finished product looks 🙂
That’s the adapting module to make the whole thing easy to connect to Arduino.
And this is the test that shows you everything works well!