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Flow rate estimation based on power
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Flow rate estimation based on differential pressure
Whether the estimate is made using the power or the differential pressure as a basis
is determined – provided a differential pressure sensor is connected – in operation by
taking into account the maximum accuracy that can be achieved with either method
under the circumstances. The best method for the purpose is selected.
Flow rate estimation based on power
The flow rate should be measured without a pressure sensor being connected. The
maximum flow rate as per the pump characteristic curve (Q 100 % = Q
max
) is 24.5 m
3
/h
Table 76: Parameters for flow rate estimation based on power
Parameter
Description
Settings
Factory setting
3-2-2-1
Setpoint unit
bar
%
3-2-2-2
Q unit
m
³
/h
m
³
/h
3-2-2-3
Pressure unit
bar
%
3-4-1-1
Q measurement
Estimated
Estimated
3-4-1-2
Q 100 % value
24,5 m
³
/h
0
3-8-2-11
AI 1 descriptor
Process
Process
3-8-3-11
AI 2 descriptor
Process
Process
3-12-1-1
Q measurement
Measured
Measured
Flow rate estimation based on differential pressure
Flow rate estimation via two pressure sensors in the discharge-side and suction-side
piping. The suction-side pressure sensor (0 - 1 bar/4 - 20 mA) must be connected to
analog input 1 and the discharge-side pressure sensor (0 - 2.5 bar/4 - 20 mA) must be
connected to analog input 2. The maximum flow rate as per the pump characteristic
curve (Q 100 % = Q
max
) is 24.5 m
3
/h.
Table 77: Parameter(s) for flow rate estimation via two pressure sensors in the discharge-side and suction-side
piping
Parameter Description
Settings
Factory setting
3-2-2-1
Setpoint unit
bar
%
3-2-2-2
Q unit
m
³
/h
m
³
/h
3-2-2-3
Pressure unit
bar
%
3-4-1-1
Q measurement
Measured
Measured
3-4-1-2
Q 100 % value
24,5 m
³
/h
0
3-8-2-1
AI 1 setting
Current
Voltage
3-8-2-4
AI1 Lo Current
4
4
3-8-2-5
AI1 Hi Current
20
20
3-8-2-6
AN IN 1 unit
bar
%
3-8-2-7
AN IN 1 Low
0
0
3-8-2-8
AN IN 1 High
1
0
3-8-2-11
AI 1 descriptor
Pressure P1
Process
3-8-3-1
AI 2 setting
Current
Current
3-8-3-4
AI 2 low curr.
4
4
3-8-3-5
AI 2 high curr.
20
20
3-8-3-6
AN IN 2 unit
bar
%
3-8-3-7
AN IN 2 Low
0
0
3-8-3-8
AN IN 2 High
2,5
0
3-8-3-11
AI 2 descriptor
P 2 pressure
Process
3-12-1-1
Q measurement
P/Q calculated
Measured
Flow rate estimation via a differential pressure sensor (0 - 4 bar/4 - 20 mA) at analog
input 2. The maximum flow rate as per the pump characteristic curve (Q 100 % =
Q
max
) is 24.5 m
3
/h.
Table 78: Parameter(s) for flow rate estimation via a differential pressure sensor
Parameter Description
Settings
Factory setting
3-2-2-1
Setpoint unit
bar
%
3-2-2-2
Q unit
m
³
/h
m
³
/h
Example
Example 1
Example 2
7 Commissioning/shutdown
PumpDrive
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