English (GB)
4
4. Application types
The booster systems are available for the following application
types:
• constant-pressure boosting
• tank filling.
Furthermore, two control variants of the booster systems are
available. The control variants are described below.
4.1 Booster system for constant-pressure applications
The booster system for constant-pressure applications is
designed to maintain a constant pressure on the discharge side
of the pumps. The booster systems for constant-pressure
applications adjust the performance according to the demand and
keep a constant pressure in the following ways:
• by cutting the required number of pumps in and out
• through continuous adjustment of the speed of the running
pumps.
4.1.1 Operating principle
The user enters the required pressure of the system (setpoint) via
the user interface of the CU 323 control unit. The CU 323 adjusts
the system performance according to the feedback received from
the pressure transmitter installed in the discharge manifold.
4.1.2 Control variants
The booster systems for constant-pressure applications are available as control variants E and ES.
Both systems work as described below.
Control variant E
Control variant ES
Two to four electronically speed-controlled pumps
One to three mains-operated pumps and one speed-controlled
pump
TM
03
09
93
09
05
TM
03
09
96
09
05
One speed-controlled pump in operation.
One speed-controlled pump in operation.
T
M
00
79
95
22
96
T
M
00
79
95
22
96
Three speed-controlled pumps in operation.
One speed-controlled pump and two mains-operated pumps in
operation.
T
M
00
79
96
22
96
T
M
00
79
98
22
96
• Control variant E for constant-pressure applications maintains
a constant pressure through continuous adjustment of the
speed of the pumps.
• The system performance is adjusted to the demand by cutting
the required number of pumps in and out and through parallel
control of the pumps in operation.
• Control variant ES for constant-pressure applications
maintains a constant pressure through continuous adjustment
of the speed of the speed-controlled pump. The other pumps
are cut in/out according to demand and to achieve a
performance corresponding to the consumption.
• The speed-controlled pump always starts first and will be the
last to stop. If the pressure cannot be maintained by the
pump, one or both mains-operated pumps will be cut in.
• Changeover among the mains-operated pumps is automatic
and depends on load, time and fault.
PT
PT
Q
H
H
set
Q
H
H
set
Q
H
H
set
Q
H
H
set
