User Manual

Functions
Additional functions
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The low humidity setpoint (%) is selectable via P026 (setpoint humidity low) and
can be adjusted via parameters in Service level or via bus.
Setting P026 to OFF (default setting) disables low humidity control. The setting
range is limited by P024.
S-Mode objects for the humidity setpoint are available when the parameter
"Humidity setpoints" is set to as group object in ETS.
When the relative humidity exceeds the high setpoint, the thermostat makes a
proportional shift of the temperature setpoint until P461 (max. shift temp setpoint)
is reached. If this control is not enough to reduce the humidity, an external
dehumidifier can be switched on via relay outputs or KNX, when the related relay
function is selected (P400, P401 or P402 is set to7).
The maximum temperature shift setpoint value is reached at setpoint humidity high
(P024) +10%. The contact for the dehumidifier is released at setpoint humidity
+15%.
Applications with a DC 0...10 V fan:
● Enable the function to control the external dehumidifier directly via relay output
by setting P400 (output Q1), P401 (output Q2) or P402 (output Q3) to 7.
When the output is energized, the S-Mode object dehumidification sends the
information "ON" to the bus
● The selected relay output is switched on if relative humidity exceeds the high
setpoint +15%.
● For applications with On/Off valves on Q1 or Q2 or both, the output Q3
(P402 = 7) is used to control the external dehumidifier.
● The relay contact remains closed or open for the minimum On/Off time defined
by P212 or P213.
Applications with a 3-speed fan:
● The external dehumidifier is controlled via external DC – On/Off converter
connected to analog output Y50. The output signal is DC 10 V if
dehumidification control is requested.
● The output Y50 remains On for a minimum time of 30 seconds (not selectable).
● This function is available without specific settings (P400, P401 and P402 are
not displayed).
The current of the external DC – On/Off converter should not exceed the maximum
output current of the Y50 (max. 5 mA). We recommend using the converter from
Titan (single relay control (IO/1RM) at 3 mA input current).
The function controls the minimum relative humidity in the room and it is available
only for applications with DC 0...10 V fan or no fan.
The external humidifier connected to the relay output is enabled as soon as the
humidity falls below setpoint humidity low (P026) and the hysteresis is ±5 %.
Setpoint high
Setpoint low
Dehumidification
Note
Dehumidification
Note
Humidification