Gira KNX 2139 00 Product Documentation page 42

Valve outputs | Channel-independent functions
￭ Deactivate the checkbox "Detect external heat requirement via object".
Detection of an external heat requirement is not possible. The actuator only
determines the heat requirement information itself.
Cyclical telegrams to the object "Heat requirement - External" with an identical
telegram polarity (ON -> ON, OFF -> OFF) cause no reaction.
After a device reset, there is no polling of the current status of the object "Heat
requirement - External". Only when a bus telegram is received does the actu-
ator take this status into account during evaluation of the heat requirement.
9.3.1.1 Heat requirement parameters
Enabling the heat requirement function
General valve outputs -> Enabled functions
Heat requirement
The heating actuator can even evaluate the command values of its outputs and
make general heat requirement available in the form of limiting value monitoring with
hysteresis (1 bit, switching). Using a KNX switch actuator, this allows the energy-effi-
cient activation of burner and boiler controllers with suitable control inputs (e.g. re-
quirement-orientated switchover between the reduction and comfort setpoint in a
central combi boiler).
Here, the heat requirement control of the actuator can be enabled centrally. The
valve outputs must be assigned to the heat requirement control individually on the
parameter pages "VOx General -> Assignments" so that they are included in the re-
quirement determination.
Setting the heat requirement function
General valve outputs -> Heat requirement
Minimum command value
The actuator only signals a heat requirement when at least one command value of
the assigned outputs exceeds the limiting value defined here plus the hysteresis
(see next parameter). A heat requirement signal is retracted when the limiting value
is reached or undershot again.
This parameter is visible only if the heat requirement function is enabled.
Hysteresis of the minimum command
value
This parameter specifies the hysteresis of the limiting value of the minimum com-
mand value of the heat requirement control. The actuator signals a heat requirement
when a command value exceeds the defined limiting value plus the hysteresis
defined here.
This parameter is visible only if the heat requirement function is enabled.
Heating actuator 6-gang with controller | Order no. 2139 00 | 21393100
Checkbox (yes / no)
0 ... 5...100 %
1...10...20 %
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