Waldbeck Huygens Mode D'emploi page 85

Now you will need to align the whole package in the proper direction by
rotating it on top of the mounting pipe as needed.Locate the arrow labeled
"North" that you will find on top of the sensor package right nextto the light
sensor. You must rotate the whole sensor package until this arrow points due
north. To achieve proper alignment, it is helpful to usea compass (many cell
phones have a compass application).
Once rotated in the correct orientation, lightly tighten the bolts a little more
(use a wrench) to prevent further rotation.
Note: Use the bubble level next to the rain sensor to make sure sensor
array is completely level. If the sensor is not level, the rain gauge, UV and
solar radiation sensors will not measure properly.
EN
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