Aligning the wmt52, Compass alignment, Figure 17 – Vaisala WMT52 User Manual
Page 38: Sketch of magnetic declination, In case the cross arm cannot be
User’s Guide ______________________________________________________________________
36 ___________________________________________________________________M210925EN-B
Aligning the WMT52
To help the alignment, there is an arrow and the text "North" on the
bottom of the sensor. WMT52 needs to be aligned in such a way that
this arrow points to the north.
Wind direction can be referred either to true north, which uses the
earth’s geographic meridians, or to the magnetic north, which is read
with a magnetic compass. The magnetic declination is the difference in
degrees between the true north and magnetic north. The source for the
magnetic declination needs to be current as the declination changes over
time.
0003-011
Figure 17
Sketch of Magnetic Declination
Compass Alignment
To align Ultrasonic Wind Sensor WMT52, proceed as follows:
1.
If the WMT52 is already mounted, loosen the fixing screw on the
bottom of the sensor so that you can rotate the device.