Dwyer 8904 - Manual (Page 14)

3 CFM (ft /min)
2 = Air Velocity (ft/min)xArea (ft )
3 CMS (m /second)
2 = Air Velocity (m/sec)xArea (m )
Cubic equations:
Units Conversion Table:
1 m/s=
1 ft/min=
1 knots=
1 km/hr=
1 mph=
m/s
1
0.00508
0.5144
0.2778
0.4464 ft/min
196.87
1
101.27
54.69
87.89 knots
1.944
0.00987
1
0.54
0.8679
1 m/s=
1 ft/min=
1 knots=
1 km/hr=
1 mph=
km/hr
3.6
0.01829
1.8519
1
1.6071 mph
2.24
0.01138
1.1523
0.6222
1
Note:
On initial start up, the unit will show full
display as fig.15
although these
features are only
available on models
8901, 04 and 06.
MIN
mil/h cfm
AVG
REC
FLOW
km/h cms
AREA
m/s
vel Hold PH Knots
ft/m 2 ft
2 m
MAX
Fig.15 13
We would suggest to set the free area
dimension before you start measuring
the air velocity so after you measure the
air velocity, you can jump to the air flow
mode to view the cubic feet per minute
without further changing the free area
dimension.
meter, position the fan and then press the
MODE key twice, you will be into the air
flow(CFM) mode and the air flow(CFM)
displayed is equal to the current air
velocity reading (FPM x FREE AREA =
CFM) times the 1.111 square feet.