Gira KNX 2139 00 Product Documentation page 131

Room temperature controller | Room temperature controller - General
triggered by a 2-point feedback control system, for this can lead to very high over-
shooting of the temperature, thus resulting in loss of comfort. When presetting the
hysteresis limiting values, you should distinguish between the operating modes.
"Heating" or "cooling" single operating modes:
In heating mode, the controller will turn on the heating when the room temperature
has fallen below a preset limit. In heating mode, the feedback control will only turn off
the heating once a preset temperature limit has been exceeded. In cooling mode, the
controller will turn on the cooling system when the room temperature has exceeded a
preset limit. The control system will only turn off the cooling system once the temper-
ature has fallen below a preset limit. In this connection, the command value "1" or "0"
will be output, depending on the switching status, if the temperature exceeds or falls
below the hysteresis limits.
The hysteresis limits of both operating modes can be configured in the ETS.
The following two images each show a 2-point feedback control for the individual op-
erating modes "Heating" (see figure 29)or "Cooling" (see figure 30). The images take
two temperature setpoints, one-stage heating or cooling and non-inverted command
value output into account.
Image 29: 2-point feedback control for the single "Heating" operating mode
Image 30: 2-point feedback control for the single "Cooling" operating mode
Heating actuator 6-gang with controller | Order no. 2139 00 | 21393100 Page 131 of 257