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Special functions
6.3. - Speed control
6.3.1. - Modes
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.
M1:
Control set to ΔT, starting from max. speed:
After the purging time the controller switches to the set max. speed. If the temperature
difference ΔT between the reference sensors (collector and storage tank) is less than
the set value, then the speed is decreased by one stage after the Sweep time elapses.
If the temperature difference between the reference sensors is greater than the set
value, then the speed is increased by one stage after the Sweep time elapses. If the
controller has adjusted the speed of the pump down to the smallest stage and the ΔT
between the reference sensors is less than ΔT off, the pump is switched off.
M2:
Control set to ΔT, starting from min. speed:
After the purging time the controller switches to the set min. speed. If the temperature
difference ΔT between the reference sensors (collector and storage tank) is greater
than the set value, then the speed is increased by one stage after the Sweep time
elapses. If the temperature difference between the reference sensors is less than the
set value, then the speed is decreased by one stage after the Sweep time elapses. If
the controller has adjusted the speed of the pump down to the smallest stage and the
ΔT between the reference sensors is below TΔoff, the pump is switched off.
M3:
Control to constant collector temperature, starting from min. speed:
The pump starts at max. speed. After the purging time the controller switches to the
set min. speed. If the temperature at the collector sensor (or relay R2 in variants with a
heat exchanger) is greater than the Setpoint, then the speed is increased. If the tempe-
rature at the collector sensor is less than the Setpoint, then the speed is decreased.
M4:
If the storage tank of the highest priority is heated to the desired temperature, then
the speed control works by variant M3. If the (secondary) storage tank of a lower priori-
ty is heated to the desired temperature, then the speed control works by variant M2.
With speed control the SRS3 E makes it possible to vary the speed of connected pumps.
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 observed!
If in doubt, the min. speed and the pump stage should generally be set to
high rather than too low.
Warning