Parameter Description
Possible settings
Factory setting
3-12-4-5
Q Lo Timeout Tm
0..120 (s)
20 s
3-12-4-6
Q Lo Timeout Function No Function
Warning
Stop and Trip
No Function
All the above parameters must be set in accordance with the pump characteristic
curve, the data sheet, and the system requirements, or the default factory parameter
settings must be checked and adjusted as required.
7.2.2.3
Flow rate
The flow rate can be estimated or measured:
▪
Flow rate estimation (for PumpDrive Advanced only) (
▪
7.2.2.3.1 Flow rate estimation (for PumpDrive Advanced only)
The Flow Rate Estimation function allows the estimated flow rate of the pump to be
displayed directly in the PumpDrive menu without the need to connect a flow rate
sensor.
The flow rate estimation results can be displayed on the control panel using the
following parameters:
▪
Parameter Sys Flow Rate (1-5-1-1) – Single-pump operation and multiple pump
operation
▪
Parameters Flow Rate Pump 1 (1-5-1-2) to Flow Rate Pump 6 (1-5-1-7) – Multiple
pump operation only
To display the current flow rate based on an estimate using the pump input power or
a differential pressure measurement, the data points of the H/Q curve and the P/Q
curve have to be set.
If the driven pump is operated outside the limits given by the set H/Q data points and
P/Q data points or if the data points have not been specified correctly , the
PumpDrive control panel will display a Q Estimate warning.
If flow rate estimation is to be used in a multiple pump configuration, make sure that
the maximum number of pumps running simultaneously
3-12-5-1
is set properly to
match requirements.
The following restrictions exist for flow rate estimation:
▪
The flow rate value cannot be output via the analog output.
▪
The flow rate estimation accuracy depends on the slope of the characteristic
curves that have been specified and can, therefore, not be provided in general
values across the board.
▪
The P and H values should be strictly monotonically rising (P) or falling (H) with
increasing flow rate Q to be able to obtain accurate flow rate estimates across
the entire speed range.
▪
If fluids with a density other than 1,000 kg/m3 are pumped, the applicable
coefficient must be set using parameter 3-12-3-2.
▪
Additional hydraulic losses between the measuring points for the suction and
discharge pressure (e.g. caused by swing check valves, long pipelines or fittings),
which are not covered by the pump's H/Q curve, will reduce the accuracy of flow
rate estimation.
▪
Flow rate estimation is not possible for simultaneous operation of twin pumps,
such as for example KSB's Etaline Z, because of the undefined position of the
changeover flap.
▪
The flow rate estimation algorithm implemented in PumpDrive (if equipped with
an Advanced control panel) has been optimised for radial flow pumps. If axial
flow pumps are used, flow rate estimation will, depending on the pump
characteristic curve, supply unusable flow rate values.
The flow rate can be estimated using two methods:
Display of flow rate
Flow rate estimation for
multiple pump operation
Restrictions associated
with flow rate estimation
7 Commissioning/shutdown
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PumpDrive
