Control of E-pumps
CR, CRI, CRN, CRE, CRIE, CRNE
13
The pump responds to the signals by adjusting its
performance up or down to compensate for the
pressure difference between the actual and the desired
pressure. As this adjustment is a continuous process, a
constant pressure is maintained in the piping system.
Fig. 9 CRE, CRIE and CRNE pumps
A CRE, CRIE or CRNE pump with integrated pressure
sensor facilitates installation and commissioning. CRE,
CRIE and CRNE pumps with integrated pressure
sensor can be set to:
• constant-pressure mode (factory setting) or
• constant-curve mode.
In constant-pressure mode, the pump maintains a
preset pressure after the pump, irrespective of the flow,
see figure below.
Fig. 10 Constant pressure mode
In constant-curve mode, the pump is not controlled. It
can be set to pump according to a preset pump
characteristic within the range from min. curve to max.
curve, see figure below.
Fig. 11 Constant curve mode
CRE, CRIE and CRNE without sensor
CRE, CRIE and CRNE pumps without sensors are
suitable for applications where
• uncontrolled operation is required
• you want to fit another sensor later in order to
control the flow, temperature, differential
temperature, liquid level, pH value, etc at some
arbitrary point in the system.
CRE, CRIE and CRNE pumps without sensor can be
set to:
• controlled-operation mode or
• uncontrolled-operation mode (factory-setting).
In controlled-operation mode, the pump adjusts its
performance to the desired setpoint, see figure below.
Fig. 12 Constant flow mode
In uncontrolled-operation mode, the pump operates
according to the constant curve set, see figure below.
Fig. 13 Constant curve mode
CRE, CRIE and CRNE pumps can be fitted with sensor
types listed on page 82.
TM
02
73
98
34
03
T
M
00
93
22
47
9
6
set
H
H
Q
TM
0
0
9
323
4
796
TM
02
72
64
28
03
TM
00
93
23
47
96
H
Q
Min.
Max.
Q
set
H
Q
H
Q
Min.
Max.