Never thought I would become an advocate of a passive shield over FARS but yesterday I started testing the passive 7714 vs 24 hr. FARS and just the first day under clear sky and light winds the 7714 ran .5 to 1° lower than the FARS all day never having afternoon spike like so many passive shields I've tested before did. I modified my shield with interior floor and roof painted flat black.
This is an inexpensive shield is why I'm excited and no moving parts.
The WMO did a study 2008-2009 using reference instruments. The passive 7714 actually got the highest 5 star rating and was cooler than reference and beat out the Davis FARS under light winds sunny conditions.
PDF of full study:
https://www.wmo.int/pages/prog/www/IMOP/publications/IOM-106_Ghardaia/IOM-106_Report.pdfSDAVIS are the 2 passive 7714 and VDAVIS are the two FARS units tested. 0 is reference, you can see both performed well but most impressive the 7714 did better which confirms what I saw yesterday.
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These are the test summaries of both shields. Low wind the FARS did well but warmer than reference when wind came up and got a 3 star rating. The passive performed well all areas and got a 5 star rating.
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