General Tools and Instruments HWA4204HA - Manual (Page 9)

7) Direction of the sensor head :
There is a mark on the top of the " Sensor Head ", When
make the measurement, then this mark should against the
measured wind, refer Fig. 6, Fig. 7. When sensor head
face against the measurement air, then the upper display
will show the air velocity value. The lower display will
show the temperature value.
sensor head ( side view )
Direction mark should face
the measured wind.
Probe Handle
Fig. 6
sensor head ( top view )
Direction mark should face
the measured wind.
Fig. 7
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