451126 Datasheet, PDF (4/10 Pages) Extech Instruments Corporation. – Vane Thermo-Anemometer Datalogger

Operation
NOTE: For all air velocity or flow measurements, the air should pass through the vane
from back to front. The rear of the vane can be found by locating the mounting nut. The
front of the vane has the engraving "ANEMOMETER". For more accurate results, maintain
a 20^o axis of air direction with the rear of the vane (refer to Fig.2).
Air Velocity
1. Power the meter by pressing .
2. Select Air Velocity measurement
function by pressing . VEL will
appear on the LCD.
Side view
of Vane
20 ^o
Air direction
20 ^o
3. Press
to select the desired unit
of measure (ft/min, mph, km/h, m/s or
knots)
Tripod mount
4. Place the vane in the air flow with the
air direction matching the direction of
Figure 2
the arrows printed on the inner walls
of the vane. If the unit does not have the printed arrows, have the tripod mount side
of the vane facing the air flow (see Fig.2).
5. Air velocity will be displayed on the bottom line of the LCD.
Temperature
1. When the meter is measuring Air Velocity, Temperature is simultaneously being
measured by the vane's built-in type-K thermocouple.
2. Press
LCD.
to select °C or °F. Temperature is displayed on the upper line of the
Air Flow
1. Power the meter by pressing
.
2. Press
to select airflow. FLOW will display.
3. Press
to select the desired unit of measure. (CFM, CMM).
4. To enter the area value, press
. The lower display line will blank waiting for
the user to program new data. Use the numeric keys to enter a new area value in
square feet. (REMINDER: if measurement is taken in inches, divide by 144 to
obtain square feet). Press
when finished.
Airflow is based on the specific dimensions of the duct being measured. For the
meter to correctly measure CFM the user must input the area of the duct. Failing to
input the correct area dimensions will result in erroneous readings.
NOTE: If the AVE or the 2/3MAX display icons are displayed in the upper left hand
corner of the LCD, press
until they extinguish.
5. Place the vane in the air flow (Fig.2).
6. Wait approximately 2 seconds for a stabilized Air Flow reading.
7. The equation below is used to calculate Air Flow:
AIR FLOW = (AIR VELOCITY) x (AREA)
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Model 451126 V2.0 6/08