HD300 Datasheet, PDF (4/13 Pages) Extech Instruments Corporation. – Heavy Duty CFM-CMM Thermo-Anemometer

Operation
Air Velocity Measurements
Side view of Vane
1. Connect the sensor to the sensor input jack on top of
the meter.
2. Turn ON the meter using the on-off button.
Arrow
3. Select the VELOCITY function using the UNITS button.
Press the button repeatedly until the LCD displays
VEL.
4. Press and hold the UNITS button for 2 seconds (until
two tones are heard) to change the temperature units
from °C to °F or from °F to °C. The LCD will reflect the
selection.
5. Select the desired air velocity units using the UNITS
button. The LCD will reflect the selection.
6. Place the sensor in the air current to be measured with
the arrow on the inlet side of the vane (see diagram).
7. View the air velocity and temperature readings on the LCD Display.
airflow
Air Flow (Volume) Measurements (CFM / CMM)
1. Connect the sensor to the sensor input jack on top of the meter.
2. Turn on the meter using the on-off button.
3. Select the FLOW mode using the UNITS button. Press the button repeatedly until the
LCD displays FLOW CFM (cubic feet per minute) or FLOW CMM (cubic meters per
minute) as desired.
4. Measure the dimensions of the duct or vent in question and calculate the area in
square feet or square meters
Note: If the dimensional measurements are made in inches (or cm), convert them feet (or
meters) before calculating the square area.
5. To begin entering the area in m² or ft² press and hold the AREA button for approx. 2
seconds (until two tones are heard).
6. Momentarily press the NEXT button to select the desired memory location to store the
area value (there are eight locations).
7. Use the
button to change the value of the flashing digit, use the button to
select another digit, and use the button to move the decimal point.
8. Press and hold the AREA button for approx. 2 seconds (until two tones are heard) to
save the area value in memory.
9. Place the sensor in the air current to be measured with the symbol on the inlet side of
the vane.
10. View the air flow and temperature readings on the LCD Display.
11. If the CFM or CMM reading exceeds 9999, the display will show the X10 or X100
multiplier in the lower right hand corner of the LCD indicating that the displayed value
must be multiplied by 10 or 100 to arrive at the correct flow measurement value.
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HD300 V2.0 11/07