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English (US)
10.2.3 Maximum pressure exceeded
This function protects the piping on the discharge side of the
booster system against damaging high pressures. The pressure
is monitored, and if the pressure is higher than 22 psi (1.5 bar)
above the setpoint for more than 5 seconds, the pumps are
stopped, the indicator light
illuminates, and the display
indicates high limit
.
When the pressure falls below the setpoint, the system will
automatically restart.
10.2.4 Low-flow operation
When only one pump is operating due to cascade, the Hydro
Multi-B will regularly check for low flow by decreasing the pump
speed.
When low flow is detected, the Hydro Multi-B will change its mode
of operation to "low-flow operation" and run in on/off mode as
described below.
In on/off mode, the system has two phases:
•
Off phase
Water is drawn from the diaphragm tank until the pressure of
the system reaches the lower limit of the on/off band
(P
set
- 0.5 x on/off band).
•
Boosting phase
The pump runs at 100 % speed until the pressure reaches the
upper limit of the on/off band (P
set
+ 0.5 x on/off band).
Fig. 9
On/off operation
11. Data communication
The CU 323 must have a CIM module (Communication Interface
Module) fitted to be able to transfer data to the SCADA system.
12. Maintenance and service
12.1 Maintenance
12.1.1 Pumps
The internal pump parts are maintenance-free. It is important to
keep the motor clean in order to ensure adequate cooling of the
motor. If the pump is installed in dusty environments, it must be
cleaned and checked regularly. Take the enclosure class of the
motor into account when cleaning.
The motor has maintenance-free, greased-for-life bearings.
12.1.2 CU 323
The CU 323 is maintenance-free. It must be kept clean and dry.
Protect it against direct sunlight. Furthermore, the CU 323 must
not be outside the ambient temperature range.
12.2 Frost protection
Pumps which are not being used during periods of frost should be
drained to avoid damage. Follow the instructions below:
1. Close the isolating valves before and after the pump.
2. Remove the filling and drain plugs.
3. Remember to open the isolating valves and refit the plugs
before the pump is put into operation again.
Do not fit the filling and drain plugs until the pump is to be used
again.
12.2.1 Taking out of operation
Switch off the main disconnect switch to take the booster system
out of operation.
Individual pumps are taken out of operation by switching off the
corresponding motor-protective circuit breaker, automatic circuit
breaker or fuse.
TM
03
92
92
48
07
PT
H
.
L
Stop = H
set
+ 0.5 x on/off band
Start = H
set
- 0.5 x on/off band
Stop
Start
H [ft]
Time [sec.]
A
B
C
B
C
A: Normal operation
B: Pressure boosting
C: Stop
Warning
Before starting work on the pumps, make sure
that the power supply has been switched off.
Lock the main switch with a padlock to ensure
that it cannot be accidentally switched on.
Warning
Ensure that the escaping water does not cause
injury to persons or damage to the motor or other
components.
In hot-water installations, special attention
should be paid to the risk of injury caused by
scalding hot water.
Warning
The conductors in front of the main switch are
still energized. Lock the main switch with a
padlock to ensure that it cannot be accidentally
switched on.
