On 5/30/2013 5:00 AM, RussellMc wrote:
>
> Hope that the water table is deep :-).
>
> Silicone Rubber is not water vapor proof and will presumably not hold
> a pressure seal either. I have NOT tested its pressure sealing ability
> but I am sure that , despite it excellent performance as a sealant,
> that it is a poor vapor seal.
>
> If you sealed a tube at the top with a solvent attached cap and added
> wire entry near the bottom you have a pressure sealed tube which water
> level "cannot" [tm] rise in.
>

The setup works fine. There are 32 of them in use for over 5 years at 4=20
dairy farms, no corrosion, no moisture issues and the area goes through=20
freeze and thaw issues all the time.  The ones installed use wifi and=20
solar to relay farm information.  Silicone works fine as a sealant, I=20
use the GE silicone.  I inspected one of the first series a month or so=20
ago because of a charging issue and all was fine except the battery=20
needed changing out. The setup is not under water, and at a depth of 2=20
feet the pressure isn't a concern.

The silicone used is this:
http://www.grainger.com/Grainger/GE-Window-and-Door-Sealant-4UH03

Mark

--=20
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