Art. No. ..5192KRMTSD
Art. No. ..5194KRMTSD
is configured, the controller will, when a button is pressed, switch to the switch-on level and
remain there until further operation occurs.
i
The parameter "Behaviour in a forced position" is not checked for plausibility, meaning that
an incorrect configuration is possible. For this reason, care should be taken to ensure that
there is no fan level in the configuration which is higher than the actual fan levels. If a
higher level is configured for behaviour in a forced position than the number of fan levels,
then the fan controller with start up the maximum possible level when the forced position is
activated.
i
The forced fan position does not influence the control algorithm integrated in the controller.
The command values of the PI feedback control continue to be transmitted to the bus, even
with a forced fan.
Command value limiting values and command value offset
In automatic operation, the command value of the controller is used internally in the device to
control the fan levels, according to the fan operating mode. As a transition between the levels,
there are threshold values, defined according to the command value of the controller, which can
be set using parameters in the ETS. The evaluation of the controller command values can be
specially influenced for automatic fan control.
The command value to be evaluated for the fan controller can be influenced by the "Command
value is 0% until internal command value is greater than" parameter in the lower command
value range. The fan controller only evaluates the command value according to the configured
threshold values when the internal command value of the controller exceeds the configured
limiting value. With smaller command values, the fan remains at a standstill.
Similarly, the command value to be evaluated for the fan controller can be limited by the
"Command value is 100% as soon as internal command value is greater than" parameter in the
upper command value range. In this case, the controller evaluates command values which
exceed the configured limiting value as 100%. This means that the fan works at full power even
with command values not at the maximum.
The "Command value offset" parameter allows configuration of a constant command value
offset for the fan. The fan controller always adds the configured offset to the command value to
be evaluated. The effect of this is that the fan turns at greater power than required by the
command value, according to the threshold values. The result of this is that, even if the
command value is switched off, the fan will continue to work when the first command value
threshold value is exceeded by the offset.
i
A configured command value offset cannot not affect a command value of greater than
100%. The maximum command value of the fan controller is therefore defined as 100 %.
Fan protection
The fan protection function allows the fan of a fan coil unit, which has not been active for some
time, to be temporarily switched to the maximum level. In this way, the controller fan motors can
be protected against stiffness. In addition, the fan blades and the heat exchanger of the fan coil
unit are protected against dust against dust.
If the fan protection is to be used, it must be enabled using the parameter of the same name in
the ETS. Fan protection can then be activated or deactivated directly using the
1-bit communication object "Ventilation, fan protection", for example using a KNX/EIB time
switch.
If the fan protection object has the switching value "1", then the fan protection function is active.
The fan then works at the highest possible fan level and overdrives automatic and manual
operation. Fan protection can then be switched off again using the "0" switching value in the
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Software "Room controller display compact module 146x11"
Functional description
