Public Lab Research note


Waterproof Housing for Arduino Conductivity Meter

by jenniferdsara | November 13, 2014 02:15 | 331 views | 3 comments | #11338 | 331 views | 3 comments | #11338 13 Nov 02:15

Read more: publiclab.org/n/11338


What I want to do

Using the Arduino Uno, we have made a device that measures temperature and conductivity for water quality monitoring purposes. Our challenge is building a container that will protect the arduino from water damage that is durable and affordable. We hope that our approach can serve others who are also trying to find ways to waterproof their devices.

Riffle-esque WQ Monitoring Calibrating Arduino-based Conductivity Meter

My attempt and results

Materials

3 in. x 2 ft. PVC Sch. 40 Pipe 3in. PVC DWV Cap 3 in. PVC DWV Hub x FIPT Female Adapter 3 in. PVC MIPT Cleanout Plug Pipe Joint Compound Silicone II Kitchen & Bath Clear Caulk w/ BioSeal Solid Rubber Stopper Stainless Steel Screws Purple Primer PVC cement

Steps

1. The PVC pipe was cut down to roughly 5 inches.
2. Outlets were made to fit thethermistor and conductivity probes (stainless steel screws) through the Cleanout Plug

IMG_2980.jpg
The hole for the thermistor was made large enough to fit a 1/2 in. x 5/16 in rubber stopper.
IMG_2860.jpg
The thermistor was threaded through the rubber stopper through a whole made with a small drill bit.
IMG_2993.jpg
Testing the thermistor & conductivity probes

3. Putting the parts together

IMG_2982.jpg

The 3in. PVC DWV Cap and PVC pipe were sealed together using Purple Primer and PVC Cement

You can follow this easy "how-to" guide for proper application of the primer and cement.

For easy access to the arduino hardware, the cap equipped with thermistor and conductivity probe screws on and off.

Questions and next steps

IMG_3061-2.jpg
To test for water leaks, we have submerged the housing(without the arduino) into a bucket of water for 24 hours. Metal chains were placed inside the housing to keep it underwater.


3 Comments

PVC pipe works well. What are you using exactly--can you post a photo?

For PVC, you can choose whatever diameter pipe you need then glue a cap on one end and a threaded fitting on the other for a removable screw cap or plug. You can get dye-free PVC primer that will remove the ink stamp on PVC as well as prep the ends for gluing without making dye marks (see http://www.mcmaster.com/#pvc-glue/=ukjt49 ). If needed, you can use anti seize compound, teflon tape and/or dow corning high vacuum grease on the threaded cap or plug if it proves difficult to remove.

Aside from DIY, the gold standard of instrument cases is probably the Pelican case, available in a variety of sizes. I wouldn't use it as a buoy but they're used for all sorts of outdoor instruments. I have a small one I take kayaking to keep my cell and wallet dry--very durable and waterproof.

see http://www.nalpak.com/Pelican-1120

Is this a question? Click here to post it to the Questions page.

Reply to this comment...


You can melt and mould milk bottle plastic if you heat it up.

Reply to this comment...


@amysoyka, do you have a reference or a research note for this? I'm wondering how clean and simple that would be. Any specific applications to waterproofing?

Is this a question? Click here to post it to the Questions page.

Reply to this comment...


Login to comment.

Public Lab is open for anyone and will always be free. By signing up you'll join a diverse group of community researchers and tap into a lot of grassroots expertise.

Sign up