40
Special functions
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7.3.8. - Solar
This function is used to control a solar pump.
7.3.8.1. - Solar
Settings range: On, Off
7.3.8.2. - Tmin S (X)
Enable/start temperature at sensor X:
If this value is exceeded at the applicable sensor X and the other conditions are also met, then the controller
switches on the associated pump and/or valve. If the temperature at the sensor drops below this value by 5°C,
then the pump and/or the valve are switched off again.
Settings range : 0°C to 40°C / Default setting: 20°C
Caution
7.3.8.3. -
∆
T Solar S (X)
Switch-on/switch-off temperature difference for sensor X :
If this temperature difference between the reference sensors is exceeded and the other conditions are also met,
then the controller switches the applicable relay on. When the temperature drops to
Δ
T Off, then the relay is
switched off.
Settings range:
Δ
T from 6°C to 20°C /
Δ
T-Off from 2°C to 19°C
Default setting:
Δ
T 10°C /
Δ
T-Off 5°C.
7.3.8.4. - Tmax S (X)
Switch-off temperature at sensor X
If this value is exceeded at the applicable sensor X, the controller switches the associated pump and/or valve
off. If the temperature falls below this value again and the other conditions are also met, then the controller
switches the pump and/or valve on again.
Settings range: 0°C to 150°C / Default setting: 60°C
With some solar systems, especially with vacuum tube collectors, it may occur that the measurement value
acquisition at the collector sensor occurs too slowly or too inaccurately because the sensor is often not at the
hottest position. When the start help is activated the following sequence is carried out:
If the temperature at the collector sensor increases by the value speci
fi
ed under “Increase” within one minute,
then the solar pump is switched on for the set “Purging time” so that the medium to be measured can be moved
to the collector sensor. If this still does not result in a normal switch-on condition, then the start help function is
subject to a 5-minute lockout time.
Start help setting range: on, off/default setting: off
Purging time setting range: 2 ... 30 sec./default setting: 5 sec.
Increase setting range: 1°C....10°C/default setting: 3°C/min.
7.3.8.5. - Start aid function
This function should only be activated by a specialist if problems arise with acquisition of measurement
values. In particular follow the instructions of the collector manufacturer.
Caution
If the set temperature difference is too small, this may result in ineffective operation, depending on the
system and sensor positions. Special switching conditions apply for speed control (see „7.2. - Speed control“
on page 32).
Temperature values which are set too high can lead to scalding or damage to the system. Scalding pro-
tection must be provided by the customer!
Danger
see „6.4. - Protective functions for Solar“ on page 30
7.3.8.6. - Protective functions
