Condensation with waterproof enclosure node

End Devices (Nodes) Hardware
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Following this Lipo/Solar Topic I created this one to separate things.

First of all, yes guys, you were right condensation happens look at this

So what can we really do? Fan? Holes to evacuate? But humidity will comme inside and damage components and solder? Coating gel on board?

I tried this one, seems to work fine but what about exposed connectors?

To be honest I never saw any outdoor sensor with fan, that’s weird, I though waterproof enclosure will close all humidity problems, seems not to be the case.

Hope we’ll find a magic idea :wink:

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I hope that will prevent condensation (part of the Solar Network Monitor)

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@ursm,
How is condensation going out? does this mean all is not “waterproof?” or air is just moving into the closed waterprof enclosure ?

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@Charles I’m blowing into the housing with the fan and the air exhausts via the three squared openings.
Yes, that mean, that the node is not waterproof, but “rainresistant” (I hope so)
I’ve chosen this, because I assume, that the solarpanel on top of the box will heat it too much.

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Got it, good catch we need to test that :wink:

but fan not really low power node, but can turn on only by day (solar active) when humidity is too much :wink:

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I’ll add a TMP36 and a MOSFET high side switch and it will only blow when the capacity of the battery is high enough or the sun is shining. main topic is not directly the condensation, but overheat …

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and a few litlle holes in the bottom, so when temp rises inside it can ‘breathe’… but this is not a final solution !

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If you think about it, Gore-Tex clothing is well know to do what we need to prevent this - let the moisture out while keeping the water/rain from coming in.

And indeed you can also get Gore vents for electronics:

https://www.gore.com/products/categories/venting

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@jmarcelino
thanks, very interesting and love this picture on their site!

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yes if that works its perfect !..

you can send an alarmsignal when there is to much condensation (If the electronics still work :wink:)
http://www.ebay.com/itm/HDS10-Moisture-Condensation-Sensor-Instead-of-HDP07-SD-1-Sensor-for-Arduino-AVR-/371147424355?hash=item566a1c4263:g:gtQAAOSwxYxUwJuw

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I think Gore vents are like £2.5 each.

Another source is Porex:

http://www.porex.com/products/electrical-electronics/vents-for-enclosure-boxes-electronics-housings/

There’s a sample request button in that page if it helps.

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I started to use “ventplugs”, pretty much like the stuff in breathable clothing - still waterproof.

http://www.wiska.com/en/products/cat/313/venting/

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@kgbvax
thanks, I’ll try some!
On conrad.de it’s 2.98€ and conrad.fr it’s 3.70€ , same reference

but they have some at tme, IP68, I ordered on TME this week and missed those one ;-(

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Another thing: I try to avoid transparent cases as I think they have more extreme temperature variations (greenhouse).
Instead I put the solar panel on the outside.
I drill holes for the wires and glue the whole panel to the case with sillicone. Works nicely even in extreme conditions (the canal water temperature sensor which is getting fully submerged from time to time. That sensor failed but the solar panel is still going good).


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@kgbvax

thanks, you’re answering to my question, “what would be closed (not clear) enclosure with solar panel outside?” I’ll give it a try :slight_smile:

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Just to dredge up an old thread and maybe help someone, I have worked and built a lot on computers for fishing boats, ships and super yachts. To protect computers from corrosion you can use a vapour phase corrosion inhibitor. A VPCI.

These are available in many different forms, from spray powder, spray liquid, to conformal coatings, gels, and devices that will for years emit a corrosion inhibitor into a confined space.

We have a great small australian company that makes VPCIs at low cost. Called Senson.
http://www.sensongroup.com/senson-tek/home (needs flash)
I use the marine guard Gel on all exposed connectors, internal and external
I use a vapaguard pad inside enclosures.
I use the Senson Electroguard Conformal Coating and paint all boards with it. Very, very good product, just don’t paint edge connectors :wink:

All the above have integrated VPCIs.

Through this combination I have made PCs that last for 5 years + in extremely poor environments (liquid salt spray in the air every day, from waves at sea!)

I use the same products to repair circuits and connectors already damaged. I clean them thoroughly then apply the products. If they still work, they then keep working, even with amazing amounts of historical corrosion! You stop the damage in its tracks.

If Australia is a bit far away from you, another global leader on VPCIs is US based Cortec corporation. They have similar products, but not quite as good IMO.

Cheers, and may your ships never sink on the great barrier reef due to corrosion from not using Senson corrosion protection products in your GPS mapping navigation computer :wink:

x

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:grin: