Useful Equations And Conversions; Battery Replacement - Extech Instruments NON-DISPLAY PORTABLE User Manual

Useful Equations and Conversions

Area equations
Rectangular Duct
Area = W x H
Cubic equations
Units Conversion Table
1 m/s
1 ft/min
1 knot
1 km/hr
1 mph

Battery Replacement

The low battery indicator appears on the LCD display when it is time to replace the 9V
battery, which powers the meter.
To replace the battery:
a. Turn the meter off.
b. Remove the battery compartment screw and remove the battery compartment
cover.
c. Replace the 9V battery and reinstall the compartment cover.
d. Fasten the compartment screw
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
FAX 781.665.0780 - TestEquipmentDepot.com
H
W
3
CFM (ft /min) = Air Velocity (ft/min) x Area (ft
3
CMM (m /min) = Air Velocity (m/sec) x Area (m
m/s ft/min
1 196.87
0.00508 1
0.5144 101.27
0.2778 54.69
0.4464 87.89
Circular Duct
A=
(A= 3.14 x R x R)
knots km/hr
1.944 3.6
0.00987 0.01829
1 1.8519
0.54 1
0.8679 1.6071
Model 451126 Version 1.6 February 2004
13
R
π 2
R
2
)
2
) x 60
mph
2.24
0.01138
1.1523
0.6222
1