Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
FAX 781.665.0780 - TestEquipmentDepot.com
above is inclusive and no other warranty, whether written or oral, is expressed or implied.
Introduction
Congratulations on your purchase of the Extech 407113 CFM meter. This handheld
meter can display Air Flow (CFM) with Area or Air Velocity with Temperature on a
10,000-count (0 to 9999) dual display LCD. Other functions include MIN/MAX
Record/Recall, RS-232 PC interface, and Data Hold. The metal vane sensor offers
rugged durability and higher temperature withstand than comparable devices. Careful
use of this meter will provide years of reliable service.
Specifications
General Specifications
Display Dual Display Multi-function 10,000-count (0 to 9999) LCD
Measurements Air Velocity: m/s, km/h, ft/min, knots, mph;
Air Flow: CMM (m
Temperature: °C and °F
Data Hold Freezes displayed reading
Sampling rate One (1) reading per second
Sensors Air velocity/flow sensor: Metal angled vane arms with low-
friction ball bearing. Temp. Sensor: Precision thermistor
MIN/MAX Records/Recalls lowest and highest readings
Auto Power OFF Automatic shut off after 15 minutes
PC Interface RS-232 Serial Communications (16-bit data stream)
Over range indication 1___ appears on the LCD
Low battery indication LBT appears on the LCD
Power supply 9V Battery (consumption 8.3mA approx.)
Operating conditions Meter: 32 to 122
Sensor: 32 to 175
Dimensions / Weight Main instrument: 7.1 x 2.8 x1.3" (180 x 72 x 32mm)
Sensor head: 2.8” (72mm) diameter
Weight 0.84 lbs. (381g) for meter and sensor
3
/min) and CFM (ft3/min);
o
F (0 to 50oC); 80% RH max.
o
F (0 to 80oC)
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Model 407113 Version 1.6 October 2005
Range Specifications
Air Velocity Measurements Range Resolution Accuracy (%rdg)
m/s (meters per second) 0.50 - 40.00 m/s 0.01 m/s ± (2% + 0.2m/s)
km/h (kilometers per hour) 1.8 – 144.0 km/h 0.1 km/h ± (2% + 0.2km/h)
ft/min (feet per minute) 100 – 7880 ft/min 1 ft/min ± (2% + 20ft/min)
mph (miles per hour) 1.1 – 89.4 mph 0.1 mph ± (2% + 0.2m/h)
knots (nautical miles per hour ) 1.0 to 78.1 knots 0.1 knots ± (2% + 0.2knots)
Air Flow MeasurementsRange Resolution Area
CMM (cubic meters per minute) 0-999,900 m3/min 0.001 to 1000 to 9,999m2
CFM (cubic feet per minute) 0-999,900 ft3/min 0.001 to 1000 to 9,999ft2
Air Temperature Range Resolution Accuracy
32 to 175oF (0 to 80oC) 0.1o F/C 1.5oF (0.8oC)
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Model 407113 Version 1.6 October 2005
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
FAX 781.665.0780 - TestEquipmentDepot.com
Meter Description
1. Sensor Input
2. RS-232 PC Interface jack
3. LCD Display
4. Keypad
5. Rubber Holster
6. Sensor
7. Battery compartment (rear)
Note: To access the rear battery compartment, first remove
the rubber holster that surrounds the meter.
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Model 407113 Version 1.6 October 2005
Operation
Air Velocity Measurements
1. Connect the sensor to the sensor input jack on top of the meter.
2. Turn on the meter using the Power button.
3. Select the VELOCITY function using the FLOW / VELOCITY button. The LCD will
display VEL when the velocity mode is selected.
4. Select the desired temperature units using the C/F select button. The LCD will reflect
the current unit selection.
5. Select the desired air velocity units
using the UNIT button. The LCD will
reflect the current unit selection.
6. Place the sensor in the air current
to be measured with the
symbol on the exhaust side of the
vane (see diagram).
7. View the air velocity and
temperature readings on the LCD
Display. The large main LCD
display shows the Air Velocity
reading. The lower LCD sub-display
shows the temperature reading.
Data Hold
1. While taking measurements, press the HOLD button to freeze the LCD reading.
2. The HOLD indicator will appear on the LCD when the display is in Data Hold mode.
3. Press HOLD again to return to normal operation.
Air Direction
Maximum and Minimum Recording
The 407113 allows the user to record and view the highest (MAX) and lowest (MIN)
readings.
1. Press the RECORD/RECALL button once. The REC indicator will appear on the
display and the meter will begin recording the MAX and MIN values.
2. Press the RECORD/RECALL button to stop the MAX/MIN recording and display the
maximum reading. The MAX indicator along with the maximum reading will appear on
the LCD display
3. Press RECORD/RECALL again to view the minimum value. The MIN indicator along
with the minimum reading will appear on the LCD display.
4. To return to normal operation, press and hold the RECORD/RECALL button for
approx. 3 seconds. The display indicators REC, MAX, and MIN will disappear.
NOTE: Placing the meter in the RECORD/RECALL mode by pressing
the RECORD/RECALL button disables the AUTO POWER OFF feature.
NOTE: Handle the vane carefully. If the metal vane blades are inadvertently
bent or damaged erroneous readings may result.
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Model 407113 Version 1.6 October 2005
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
FAX 781.665.0780 - TestEquipmentDepot.com
Air Flow (Volume) Measurements (CMM / CFM)
1. Connect the sensor to the sensor input jack on top of the meter.
2. Turn on the meter using the POWER button.
3. Select the FLOW mode using the FLOW/VELOCITY button. The LCD will display
FLOW CFM or FLOW CMM when the flow function has been selected.
4. Select the desired air flow units: CMM (cubic meters per minute) or CFM (cubic feet
per minute) using the UNIT button. The LCD will reflect the selection.
5. Measure the dimensions of the duct or vent 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.
6. Press the AREA button to begin entering the area in m
2
or ft2. Use the button to
increment the flashing digit, use the button to decrement, use the button to select
the next digit, and use the button to set the decimal point.
7. Press the ENTER/RESET button after the area value has been entered. The bottom
display will indicate the area entered in ft
2
or m2. The main LCD displays the Air Flow in
CFM (cubic feet per minute) or CMM (cubic meters per minute). If the CFM or CMM
reading exceeds 9999, use the displayed X10 or X100 multiplier to calculate the
reading.
8. Note that for FLOW measurements, three modes apply: The normal, default mode,
where the actual flow is indicated and the two modes described below under 2/3 MAX
Flow and AVG Flow.
Note: The temperature function is not active in the FLOW mode.
2/3V MAX Flow Mode
In this mode the meter will display two-thirds the measured Flow (Volume). To access this
mode, ensure that the meter is in the FLOW mode (via the FLOW/VELOCITY button) and
then press the FLOW MODE button until the 2/3V MAX display icon appears. Now the
Flow display will be 2/3 the actual measurement. To return to the normal display mode,
press the FLOW MODE button until the 2/3VMAX and the AVG icons switch off.
AVG (Average) Flow Mode
In this mode the meter will display the AVERAGE Flow for up to 20 readings. To access
this mode, ensure that the meter is in the FLOW mode (via the FLOW/VELOCITY button)
and press the FLOW MODE button until the AVG display icon appears. Now each time the
AVG/START button is pressed a reading will be taken and averaged. The lower LCD
display becomes a 20-reading counter and with each reading taken the counter is
incremented. Allow 3 or 4 seconds between AVG/START button presses for the display
counter to update. The main LCD displays the averaged Air Flow value. To return to the
normal display mode, press the FLOW MODE button until the AVG icon switches off.
RS-232 PC Interface
The 407113 is equipped with a 3.5mm phone jack (meter top) for connection to a PC for
data acquisition purposes. To obtain PC interface cabling and Windows
TM
data acquisition
software (Model 407001), contact Extech Instruments or an authorized distributor.
Instructions for use are provided with the data acquisition software/hardware kits.
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Model 407113 Version 1.6 October 2005
Battery Replacement
When the LBT icon appears on the LCD, the 9V battery must be replaced.
1. Remove the rubber holster that surrounds the entire meter
2. Slide off the rear battery compartment
3. Replace the 9V battery
4. Affix the battery compartment cover and the meter holster
Useful Equations and Conversions
Area equation for rectangular or square ducts
Width (W)
Height (H)
Area equation for circular ducts
Radius
Cubic equations
CFM (ft3/min) = Air Velocity (ft/min) x Area (ft2)