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Old 10-20-12, 10:45 AM   #15
Xringer
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Default 950 nm

Quote:
Originally Posted by Mikesolar View Post
The Sanyo is definitely in the open, where my coil is entirely within a cabinet and only subject to reflected light, if at all. I think the tuning can be made to avoid it but it needs to be quite precise which is why 2 parallel systems might work. Temp measuring to determine turn on and IR to determine when it has defrosted, for example.

That Sanyo is in the open, but it's installed next to a wall and there is no way
that direct sunlight could get back there and into the sensor.
Sanyo #2 is on the north side of the house and it's even darker behind it.

From what I can tell about indirect sunlight, so far, the day and night difference in signal voltage levels will be very slight.


A fully inclosed HX like yours is the idea solution to solar pollution..

The sensor spec says "• Daylight blocking filter • Emitter wavelength: 950 nm"
950 nm isn't in the power band of the sun.. It looks like visible light is where the peak is..


Edit: Found this doc..
http://www.ro.feri.uni-mb.si/predmet...pplication.pdf
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Last edited by Xringer; 10-20-12 at 11:43 AM.. Reason: pdf link
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