EF200R-C
12
Upper range value
The measuring signal amplitude must be below a certain limit value to ensure that the signals can be
evaluated without error. This results in a maximum permitted flow rate Q
AmpMax
:
Q
[m /h] =
AmpMax
³
350 [m/s] · · D [m]
i
²
π
· 3600 [s/h]
4 ·
³]
m
/
g
k
[
ρ
³]
m
/
g
k
[
1
Q
[ /min] =
AmpMax
³
1148 [ /s] · · D [ft]
i
²
π
· 60 [s/min]
4 ·
0.0624 [lbm/ ]
³
A0034316
Q
AmpMax
Maximum measurable flow rate based on signal amplitude
D
i
Internal diameter of measuring tube (corresponds to dimension K→ See page 41)
ρ
Density
For gas applications, an additional restriction applies to the upper range value with regard to the
Mach number in the measuring device, which must be less than 0.3. The Mach number Ma describes
the ratio of the flow velocity v to the sound velocity c in the fluid.
Ma =
v [m/s]
c [m/s]
Ma =
A0034321
Ma
Mach number
v
Flow velocity
c
Sound velocity
The corresponding flow rate can be derived using the nominal diameter.
Q
[m /h] =
Ma = 0.3
³
0.3 · c [m/s] · · D [m]
i
²
π
4
· 3600 [s/h]
Q
[ /min] =
Ma = 0.3
³
0.3 · c [ft/s] · · D [ft]
i
²
π
4
· 60 [s/min]
A0034337
Q
Ma = 0.3
Restricted upper range value is dependent on Mach number
c
Sound velocity
D
i
Internal diameter of measuring tube (corresponds to dimension K→ See page 41)
ρ
Density
