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Special functions
(only
STDC
version 2, 3 and 4)
If the speed control is activated, the
STDC
makes it possible to vary the speed of standard
pumps at relay by means of special internal electronics.
7.3. - Speed control
This function should only be activated by a specialist. Depending on the
pump and pump stage used, the minimum speed should not be set too
low, because otherwise the pump or the system may be damaged. The
information provided by the relevant manufacturer must also be ob-
served! If in doubt, the min. speed and the pump stage should generally
be set too high rather than too low.
Caution
(only
STDC
version 2, 3 and 4)
The following speed variants are available here:
Off:
There is no speed control. The connected pump is only switched on or off with full
speed.
Mode V1:
After the purging time the controller switches to the set max. speed. If the
temperature difference ∆T between the reference sensors (collector and storage tank)
is smaller than the set value ∆T R1, then the speed is decreased.
If the temperature difference between the reference sensors is greater than the set
value (Switch-on temperature difference ∆T R1), then the speed is increased. If the
controller has adjusted the speed of the pump down to the smallest stage and the ∆T
between the reference sensors is ∆T off, the pump is switched off.
Mode V2:
After the purging time the controller switches to the set min. speed. If the
temperature difference ∆T between the reference sensors (collector and storage tank)
is greater than the set value, then the speed is increased. If the temperature difference
∆T between the reference sensors is below the set value, then the speed is decreased.
If the controller has adjusted the speed of the pump down to the smallest stage and
the ∆T between the reference sensors is T∆off, the pump is switched off.
Mode V3:
After the purging time the controller switches to the set min. speed. If the
temperature at the reference sensor (collector, in systems with heat exchanger on
relay 2 the heat exchanger instead) is greater than the setpoint to be set subsequently,
then the speed is increased. If the temperature at the reference sensor (collector) is
less than the setpoint to be set subsequently, then the speed is decreased.
Setting range: V1,V2,V3, off/default setting: off
7.3.1. - Speed control mode