KROHNE IFC 110 Converter - Manual (Page 61)

Part C Special applications, functional checks, service, and order numbers Sect. 6.5
05/2003 IFC 110 F 61
6.5 Pulsating flow
Application
Downstream of positive displacement pumps (reciprocating or diaphragm pumps) without
pulsation damper.
Resetting the signal converter, see Sections 4 and 5.
Changing the settings
• Fct. 3.02 FIELD FREQ. (change the magnetic field frequency)
– Stroke frequency less than 80 strokes/min. (at max. pump lift), do not change setting.
– Stroke frequency 80-200 strokes/min. (at max. pump lift), change setting to 1/2,
only recommended for PROFIFLUX 5000 F (DN 2.5-100 and
1
/
10
”-4”)
and ALTOFLUX 4000 F (DN 10, 15, 50-100 and
1
/
10
”,
1
/
2
”, 2”-4”),
for other types and sizes please consult factory.
– Please note: at stroke frequencies near the limit of 80 strokes/min. additional measurement
deviations of ± 0.5 % of the measuring value may occur occasionally.
• Fct. 3.06 APPLICAT. (adapt modulation limit of A/D converter to the application)
Change setting of subfunction ”FLOW” to ”PULSATING”.
• Fct. 1.04 DISP. FLOW (change display of flow)
Change setting to ”BARGRAPH” in order to be able to evaluate the display ripple.
• Fct. 1.02 TIMECONST. (change time constant)
– Change setting to ”ALL” and set time (t) to seconds.
1000
– Recommendation: t [s] =
min. number of strokes/min.
– Example:
min. number of strokes during operation = 50 strokes/min.
1000
t [s] =
50/min.
= 20 s
With this setting, the residual ripple of the display is approx. ± 2 % of the
measuring value. Doubling the time constant reduces the residual ripple of
the display by a factor of 2.