Art. No. ..5192KRMTSD
Art. No. ..5194KRMTSD
Switch-on level
The fan can, if it was switched off before and should now start up, be switched on at a defined
switch-on level. This switch-on level can be any of the available fan levels, and is set in the ETS
using the "Start-up via level" parameter. The switch-on level is generally one of the higher fan
levels of a fan coil unit, so that at the beginning of a heating or cooling process the fan can start
up correctly (reliable start-up of the fan motor through transfer of a higher torque, and thus a
higher fan speed).
The switch-on level remains active for the "Waiting time on level change-over" configured in the
ETS. In automatic operation, the controller only switches to the fan level specified by the
command value, when the waiting time has elapsed. There is no change-over if, after the
waiting time has elapsed, the fan level specified by the command value equals the switch-on
level.
i
If the controlled fan requires a longer period of time for the start-up, then the waiting time in
the ETS should be configured to higher values (possible time range 100 ms ... 25.5 s). It
should be noted that the waiting time is also taken into account on each level change-over
in automatic operation!
The switch-on level is always taken into account by the fan controller in automatic mode on
switching the fan on (if it was previously switched off by the command value evaluation) and, in
certain situations, after activation of manual operation. On changing over to manual operation,
the behaviour of the fan depends on the settings of the parameter "Fan level on changing over
to manual" and "Start-up via level" and the previous fan level in automatic operation as follows...
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If, due to the "Fan level on change-over to manual" parameter, a defined level from level 1
to level 8 is requested, the controller will set this level on activating manual operation. In
this case, the parameter "Start-up via level" is not taken into account if the fan was most
recently switched off in automatic operation.
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If, due to the "Fan level on change-over to manual" parameter, "Fan level OFF" is
requested, the controller will switch the fan off during the change-over to manual operation.
On subsequent pressing of the button for manual control, the "Start-up via level" parameter
is taken into account and the switch-on level set. Then, the controller waits in this level until
further manual operation.
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If, due to the "Fan level on change-over to manual" parameter, no defined level is
requested ("No change" setting) and the fan was switched off during automatic operation,
then it will remain switched off on changing over to manual operation. On subsequent
pressing of the button for manual control, the fan is switched to the first level. The "Start-up
via level" parameter is thus not taken into account.
i
A configured switch-on level is applied directly without a waiting time.
i
With a fan change-over via the 1-bit objects, when the fan level is changed by the
controller, the active fan level is first switched off before the new level is switched on. In this
case, the switch-off of a fan level and the subsequent changeover to a new fan level is not
evaluated as a fan start-up, also meaning that the switch-on level is not set In automatic
operation, the switch-on level is only taken into account if the fan was switched off
previously by the command value evaluation (command value < level 1 threshold value
minus hysteresis) and then it is to start up using a new command value.
i
The start-up via the switch-on level also takes place after a change-over from manual
operation to automatic operation, providing that the fan was most recently switched off in
manual operation and, in automatic operation, a new command value requires the fan to be
switched on.
Page 150 of 309
Software "Room controller display compact module 146x11"
Functional description