Water sensor for enclosure

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I reworked the gasket on my enclosure over the weekend. The weather is gloomy these days and though I generally try to avoid riding in rain, avoiding wet roads is almost impossible. I believe my enclosure is now fairly water resistant but I still don’t trust it 100%. I was thinking it would be great to have a simple way of checking that no water got in. For piece of mind if it didn’t and for taking a quick action if it did. There are some dead cheap (~$2 shipped) modules available on AliExpress and alike. I plan to order one and do some experiments. Has anyone played with these modules before?

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This is a brilliant idea, I look forward to seeing what you do with it. It would be really cool if davega could warn me about moisture in my enclosure.

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How would indication look like? A LED which switch on as soon as the sensor detect something?

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I have, (and I’m guessing most ppl that has done some basic electronics labs has as well)
They work great, problem is that they’re very binary, its either water or no water. Getting them dry to stop triggering takes forever unless you wipe em down. But maybe thats the entire point?

Maybe a humidity sensor would be an option as well? (depending on your goal ofc)

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Ideally you would have need sensor lines around the the entire perimeter which would detect intrusion from any side.

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I just superglue rice along the perimeter of my enclosure. If I smell rice ready to eat, I know there’s been a breach.

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I have too and as @linsus states, they are better used in a binary fashion (which may be fine for this purpose) than as an gauge of water levels

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We should use small amounts of potassium in the same manner. If its on fire you know water got in there.

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You can get stickers that turn red when they get wet, but that’s only useful if you open the enclosure I guess

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Just use a pouch styled lipo with a small slit :stuck_out_tongue: Should give you the same type of warning

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Or maybe fill the enclosure with silica?

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Those water sensors tend to require quote a bit of water. If you’ve got enough in your enclosure to trigger it, there’s probably already to much in there.
I like this ideafor an early warning System as long as you don’t live in the tropics

Make sure it has RH Up to 100%

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Possibly a combination of humidity and liquid water sensors would be best?
I imagine an enclosure with channels in the bottom to encourage water to pool near the sensor.

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Personally I think if you get to the point where there is liquid water inside your enclosure then it’s already to late.

My recommendation would be to look into humidity sensors rather than water sensors as it won’t require contact with water droplets to tell you there is a leak.

I would suggest something like the dht11 or dht22 as a cheap option or something like sht35 as a higher quality alternative.

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Something like this around the openings of the enclosure might work.

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Speaking of water ingress, I had a random idea one time to “waterproof” an enclosure in extreme environments (not really practical unless you want to ride in a downpour). A positive air pressure system, basically, taking a very tiny squirrel cage turbine to push a couple PSI of air pressure into an enclosure from the top, the intake of the fan will have dust and water trap so the air that is pushed into the enclosure is clean and dry. The air pressure in the enclosure will force it’s way out of any gaps/openings, keeping a constant airflow of air exiting all potential leak points, so water can never get in as long as the turbine is on.

To make it even more extreme, a low point can be set in the enclosure with a tiny vent so any bits of water will be immediately ejected, and depending on the the height of the intake vent and the pressure the fan can maintain, the board may even be operable through shallow water crossings.

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