[TowerTalk] Condensation Inside Tower Cable Box

[Shawn Donley]

Thought I'd re-post with the solution to the problem described below.  I mounted a small (~ 2") 12vdc muffin fan on the underside of the box using an enlarged hole that was for an extra cable.  The fan blows outside air into the box.  The air must escape via space between the cables and grommets, but likely more via the PVC conduit for my underground cables.  Seems to have completely eliminated the condensation problem so far.  Completely dry inside now.

N3AE

> Date: Mon, 16 Oct 2023 14:56:37 -0400 (EDT)
> From: Shawn Donley <n3ae at comcast.net>
> To: "towertalk at contesting.com" <towertalk at contesting.com>
> Subject: [TowerTalk] Condensation Inside Tower Cable Box
> Message-ID: <159386131.427573.1697482597363 at connect.xfinity.com>
> Content-Type: text/plain; charset=UTF-8
> 
> Hello fellow TowerTalkers,
>  
> I have an aluminum outdoor electrical enclosure at the base of my tower.  My underground runs of hardline enter the box through a PVC conduit elbow entering at the bottom of the enclosure.  The tower coax and rotor cables exit the bottom as well.    In humid weather, especially this time of year when the temperature goes down at night, I get a significant amount of condensation inside the enclosure, not only on the enclosure but on the outside of the cables within it.  Enough water to make one think there's no environmental protection provided by the enclosure in the first place.  I suspect the moist air from the conduit is the source since the underground run uses slotted corrugated drain pipe covered with a soil sock rather than solid wall PVC.   Why ... concerns of long term condensation inside solid conduit...another subject thoroughly discussed elsewhere and hopefully not again on this thread.
>  
> Has anyone experienced something similar and has a proven fix?   I considered a small 12v box fan to circulate some outside air through the enclosure but I think the cold box walls would just condense that moist air as well.  Perhaps a low wattage 12v light bulb inside the enclosure to provide some heat to keep the walls warmer?  Some water pipe heat tape on the outside of the box (but I would like to avoid any 125vac solution)?  Sealing the entry conduit is problematic with the several cables of different diameters.  I would not want to "foam" the conduit with expanding foam or something like that which would make pulling a new cable much more difficult.
>  
> tnx
> N3AE