[RE-wrenches] raintite box mounting angle

[Wind-sun.com]

It is almost impossible in a normal installation to get a totally waterproof enclosure.

What you describe with the flooded box is more common than people might think. 

What causes most of that is condensation. Humid air gets sucked into the enclosure at night or whenever else it cools off. The water then condenses inside. Next day, the box heats up again and the air expands a bit again, but the water has already condensed and cannot get out.

That is why the weep hole as you noted is mandatory, especially in areas with high humidity. But we have seen this even in the desert regions of Arizona and CA, so it can happen anyplace over long periods of time.

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Northern Arizona Wind & Sun - Electricity From The Sun Since 1979
Solar Discussion Forum: http://www.wind-sun.com/ForumVB/
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  ----- Original Message ----- 
  From: Jeff Yago 
  To: kirk at vtsolar.com ; RE-wrenches 
  Sent: Tuesday, August 25, 2009 8:40 AM
  Subject: Re: [RE-wrenches] raintite box mounting angle



  I am getting more convinced that there is no such thing as a water-tight electrical enclosure, regardless of gasket covers and sealed openings.  We always drill a very small "weep-hole" in the bottom of an enclosure.   We have found this is too small to allow insects to enter, but will drain any leaks or moisture that gets condensed into a liquid.  I was recently called by the owner of a large pole mounted array (that was installed by another firm ) when the system stopped working and the originally installer was long gone.   I absolutely swear to you that when I pulled the covers off several electrical junctions boxes, water POURED out of the enclosures!   I am not talking about wet, I am saying about a quart of water was being held inside each enclosure by their water-proof gasketed covers.  Needless to say, all of the electrical terminals and wire connectors inside these junction  boxes were badly corroded.

  I know they make totally water-proof electrical equipment for under-water applications, but have found most outdoor rated electical enclosures will get some water inside and that includes under-ground conduit.   Take some advice and regardless of mounting orientation, drill a small weep-hole in the bottom if there is not one provided by the manufacturer.

  Jeff Yago
  DTI Solar

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