Fluke IRR2-BT User Manual page 9

Inclination and Cardinal Direction
Place the Meter directly onto the PV panel to get accurate tilt. For
surfaces of rooftops with inclinations different than 0°, push
for 2 seconds to reset the angle and measure the true inclination
of a solar panel. Secure a probe to the solar panel with optional
electrical or similar tape to assure reliable mounting.
The compass measurement requires a two-step process for
accurate cardinal direction.
1. Do irradiance, temperature, and inclination measurements with
Meter placed on and aligned with the PV panel. The compass
function shows --- on the LCD when the tilt angle is above
20 degrees. At a tilt angle of >20 degrees any compass
reading shown will be inaccurate due to the influence by
surrounding metal objects.
2. Do the compass measurement away from the PV panel by
holding the meter or placing meter on a horizontal surface
(0 degrees to 20 degrees tilt) pointing the tip of the meter in
the direction that the PV panel faces. Keep away from any
metal objects.
The compass measurement is in reference to magnetic
north. The measurement is unreliable if the Meter is
placed on or near objects containing metal (such as solar
panels, metal roofs, and concrete surfaces with rebar).
≤ 90°
Note
N
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