[Weather] 1-wire humidity sensor for outdoor use?

[Dave McGuire]

On Nov 29, 2006, at 1:59 PM, Karl Uppiano wrote:
>>> I have had good results with mine once I shielded it from the   
>>> light. I
>>> found
>>> that even indirect sunlight on a bright sunny day -- even inside a
>>> radiation
>>> shield -- would cause the sensor to get all flaky. I put a small   
>>> piece
>>> of
>>> black heat shrink tubing over it, leaving openings at each end  
>>> for  the
>>> air
>>> to circulate (i.e., I did not shrink the tubing, I just allowed  
>>> it  to
>>> remain
>>> loose). This sensor has been in place for about 18 months, and the
>>> original
>>> one might have been OK too, if I had shielded it from the light.
>>
>>   The datasheets even state that the component is light sensitive.
>
> Yes, however, I was surprised how light sensitive. IIRC, the data  
> sheet said
> avoid direct sunlight, but mine was affected by indirect sunlight.  
> I'm just
> saying, if your sensor is flaky, make it *really* dark.

   Ahh ok, I see what you mean.  Yes, the degree of photosensitivity  
is surprising.  Making it really dark while still ensuring adequate  
environmental exposure can be difficult.  I wonder if it'd be useful  
to mount it in the middle of a small serpentine tube, open at both  
ends, with a small fan to push air through it lightly.

               -Dave

-- 
Dave McGuire
Cape Coral, FL