Abstract: It was recently discovered that our transmitter is no longer sending data and that the last reading on the humidity sensor was 100%. I wonder what happened? We are now moving ahead in the design process to create a waterproof system. 

Objective: I intend to describe design considerations and current ideas that have come up to design the new enclosure for the evaporimeter base. 

Materials and Methods: 

This the new concept for the evaporimeter:

Screen Shot 2017-10-04 at 10.33.40 AM.png

The idea of the new base is to have a case that consists of a main body and cap. I think it is a good idea to use a rubber gasket to seal the junction between the two. In terms of materials, I plan to keep on using ABS for the time, but using T-Glase, Bridge, or Nylon is also recommended to keep water from entering into the 3d printed case.

We also need to run some wire into the casing from the sensors on the outside. Using a coupling mechanism would be our best solution. The only problem is that our system is very small and the coupling mechanisms for that scale are very expensive, about $40 per set. Another solution that was brought up was to use rubber sheet and perforate a small hole to run the wire through. This rubber sheet will seal up against the wire and keep moisture out. We are also leaning towards using a cordgrip and using a 4 wire cable. Another solution was to find some type of waterproof ethernet cable.

Results

For now, we will be testing the cordgrip and ethernet options. These seem to be the most inexpensive options. I will also be ordering the rubber gasket to get a good seal for the base case. 

Links

Coupling Mechanism

Example Cordgrip

Rubber Seal