salmson CC HVAC Instrucciones De Instalación Y Funcionamiento página 35

ENGLISH
The parameter settings required for switching the peak-load
pump on or off (switching level ➄/➅; delay times) can be
made in Menu 4.3.3.1.
In order to avoid actual value peaks when switching on or
actual value drops when switching off a peak-load pump, the
speed of the base-load pump can be reduced or increased
during these switching operations. Corresponding settings for
the frequencies of this "peak filter" can be made in Menu
4.3.5.1 – page 2.
Normal operation of switchgears without frequency converter
(see Fig. 4)
The controlled variable is also formed by setpoint/actual value
comparisons in cases of switchgears without or with disrupted
frequency converters. However, because a load-sensitive
speed adjustment of the base-load pump is not possible, the
installation functions as a two-point controller between ➄ and
➅.
The switching on and off of the peak-load pump proceeds in
the manner described above.
Pump duty cycling
Various pump alteration mechanisms are applied in order to
ensure that the loads on all the pumps are as uniform as possi-
ble and to equalise the running times of the different pumps.
The corresponding settings can be made in Menu 4.3.4.2.
If an alteration of the pumps is selected as a function of oper-
ating hours, then the installation will define the base-load
pump by means of the operating hours counter and the pump
diagnostics (faults, enablement) (service life optimisation). The
time to be set for this pump alteration mode expresses the
maximum permissible running time differential.
Cyclical pump alteration (works setting) replaces the base-
load pump after the expiration of the set period. The operating
hours are not taken into account thereby.
When the Impulse alteration mode is selected, the base-load
pump is changed with each new demand.
Neither here the operating hours are nor taken into account.
The Operating hours and Impulse alteration modes are contin-
gent on a preceding stop of the installation (e.g. by "External
OFF").
In the menu item Pump preselection a particular pump can be
permanently determined as the base-load pump.
The peak-load pumps are altered in accordance with opti-
mised running times, independent of the pump alteration
mode for the base-load pump. This means that the pump with
the lowest running time is always the first one to be switched
when there is a pump demand and the last one to be switched
off as demand drops.
Standby pump
A pump can be defined as a standby pump in Menu 4.3.4.1.
The activation of this operating mode means that a pump will
not be actuated in normal operation. It will be switched only if
a pump is switched off due to a fault. The standby pump is
however subject to standstill monitoring and is included in the
test run. Service life optimisation ensures that every pump will
act as a standby pump.
Pump test run
A cyclical test run of the pumps is provided in order to avoid
long standstill periods. The a particular pump can be perma-
nently determined as the base-load pump between 2 test runs
and the duration of the test run can be defined in Menu 4.3.4.3
for this purpose. A waiting period of 0 hours deactivates the
test run.
Fault-actuated switchover multi-pump system
•Installations with frequency converter:
If the base-load pump has a fault, then it will be switched off
and the one of the peak-load pumps will be switched to the
frequency converter. A fault in the frequency converter
switches the installation over to the "Auto without frequency
converter" operating mode with the associated regulation
behaviour.
•Installations without frequency converter:
The installation is switched off in the event of a fault in the base-
load pump and one of the peak-load pumps is governed as a
as base-load pump for control functions. A fault in one of the
peak-load pumps will always switch it off and cut-in a different
peak-load pump (or also the standby pump if necessary).
Frost protection (not with p-c control mode)
A frost protection signal can be fed to the control system
through a normally closed contact via the signal of a frost pro-
tection thermostat. If the signal input is opened, then this will
lead to an immediate activation of one pump with adjustable
speed (see Menu 4.3.5.1).
Depending on the selected acknowledgement mode (see
Menu 4.3.2.4), the installation will return to the prescribed auto-
matic mode following the closing of the normally closed con-
tact or a manual acknowledgement is required.
Frost protection operation is possible only if the installation is
switched off by setpoint 2 or 3, analogue external setpoint or
External Off.
Monitoring of maximum and minimum values (only for p-c and
temperature control modes)
The limit values for safe system operation can be set in
Menu 4.3.2.2.
A hysteresis for the corresponding values and a time interval
before the triggering of fault processing can be entered for the
monitoring of maximum and minimum values in Menu 4.3.2.2.
This is intended to allow hiding short-term measurement value
peaks and drops, among other things.
External OFF
It is possible to deactivate the control device by means of a
normally closed contact. This function has override priority; all
pumps will be switched off. The pump test run remains active.
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