English
Installation and operating instructions Wilo-Control CC-Booster
7
NOTICE:
After connecting the switchgear to the supply
voltage, as well as after every mains interruption,
the switchgear returns to the operating mode set
before the power interruption.
6.2.1 Switchgear operating modes
Normal operation of switchgears with fre
-
quency converter - CC-FC version (see Fig. 2)
An electronic signal transmitter (measurement
range to be set in menu 4.3.2.3) supplies the con
-
trol variable actual value as a 4...20 mA current
signal. Then the controller maintains the system
pressure constant by means of the comparison of
the setpoint/actual value (for setting of the refer
-
ence setpoint
›
see menu 3.1).
If there is no "external off" signal and no fault, the
base-load pump with load-sensitive speed con
-
trol starts when its start level
œ
is undershot.
If the power requirement cannot be met by this
pump, the switchgear switches on a peak-load
pump and, if the requirement increases further,
other peak-load pumps (start level:
Ÿ
). The peak-
load pumps run at constant speed, the speed of
the base-load pump is controlled to the
setpoint
¢
in each case.
If the requirement drops until the controlling
pump is working in its lower performance range
and no peak-load pump is required any longer in
order to meet the requirement then the peak-load
pump switches off (stop level:
¡
)
.
The base-load
pump switches off independently via the zero-
flow cut-off (stop level:
ž
). If the pressure drops
again below the start level
œ
, then the pump
restarts.
The parameter settings required for switching on
and off the peak-load pump (switching level
Ÿ
/
¡
; delay times) can be set in menu 4.3.3.2. A
selection can be made between the same switch-
off level for all pumps and pump-specific switch-
off level. The system suggests pump-specific
switch-off levels. For this it is necessary to enter
Q
nom
and H
0
in menu 1.2.
To avoid pressure peaks when switching on or
pressure troughs when switching off a peak-load
pump, the speed of the base-load pump can be
raised or reduced during these switching opera
-
tions. Corresponding frequency settings of these
so-called peak filters can be undertaken in
4.3.5.1 – page 2.
Normal operation of switchgears without
frequency converter – CC version (see Fig. 3)
The controlled variable is taken from comparison
of the setpoint/actual value for switchgear with
-
out a frequency converter (mains operation) or
with a faulty frequency converter. Because there
is no possibility of load-sensitive speed adapta
-
tion of the base-load pump, the system works as
a two-point controller between
œ
/
ž
or
Ÿ
/
¡
.
The peak-load pump is activated and deactivated
in the manner described above.
For switching off the base-load pump, a separate
switching threshold
ž
can be set in menu 4.3.3.1.
Normal operation of switchgear in the CCe ver
-
sion (see Fig. 4)
A selection can be made between 2 operating
modes for switchgear in the CCe version. The set
-
ting parameters described for switchgear CC…FC
are used each time for this.
The cascade mode corresponds in its operation to
the normal operation of switchgears in the CC…FC
version (see Fig. 2), whereby the peak-load pumps
are activated with maximum speed.
In Vario mode (see Fig. 4), one pump starts as a
load-sensitive speed-controlled base-load pump
(Fig. 4a). If the required power requirement can no
longer be met by this pump at maximum speed,
another pump starts and takes over the speed
control. The previous base-load pump continues
at max. speed as a peak-load pump (Fig. 4b). This
procedure is repeated at increasing load until the
maximum number of pumps is reached (here:
3 pumps – see Fig. 4c).
If demand falls, the controlling pump will be
switched off when the minimum speed is reached
and a former peak-load pump takes over control.
The switchgear has the following additional oper
-
ating modes whose parameterisation is described
on the user interface:
Zero-flow cut-off
To avoid the pump running without water con
-
sumption, the switchgear performs a zero-flow
test that may lead to pump deactivation where
necessary.
Pump cycling
Various pump cycling mechanisms are used selec
-
tively to ensure that the load is distributed as
evenly as possible between all pumps and to
thereby balance the running times of the pumps.
Standby pump
One pump can be defined as the standby pump
and is available in the event that another pump
fails.
Pump test run
To avoid longer standstill times, a cyclic test run of
the pumps is provided.
