KROHNE IFC 110 Converter - Manual (Page 79)

Part C Special applications, functional checks, service, and order numbers Sect. 7.7
05/2003 IFC 110 F 79
Example
Full-scale range Q
100%
= 200 m³/h (Fct. 1.01)
Meter size DN = 80 mm = 3 inch (Fct. 3.02)
Current at Q
0%
I
0%
= 4 mA
Q
100%
I
100%
= 20 mA
}
(Fct. 1.05)
Pulses at Q
100%
P
100%
= 200 pulses/h (Fct. 1.06)
Flow sensor constant GK = 3.571 (see instrument nameplate)
Constant (V in m³)
(t in h) K = 7074 (see table)
(DN in mm)
Calculation of ”X” and setting of ”Y”
Q
100%
x K 200 x 7074
X =
GK x DN
2
=
3.571 x 80 x 80
= 61.905
Y = 80, setting of switch Y, see GS 8 A front panel
(comes closest to the value of X and is smaller than X).
Calculation of setpoint readings I and f
Y 40
I = I
0%
+
X
(I
100%
- I
0%
) = 4 mA +
61.905
(20mA - 4mA) = 14.3mA
Deviations are permissible between 14.1 and 14.6 mA (equivalent to ± 1.5 %).
Y 40
f =
X
x P
100%
=
61.905
x pulses / h = 180.9 pulses/h
Deviations are permissible between 178.2 and 183.6 pulses/h (equivalent to ± 1.5 %).
If you need to return your flowmeter to KROHNE,
please refer to the last-but-one page of these instructions.