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Temperature Coefficient Regulation
Options:
±0,1°C….±0,3…..±1,0°C
With this parameter is possible to select a level for the hysteresis (±
∆
T) by
which the setpoint fluctuates.
The HVAC plant is switched ON in case of an ON/OFF control when
temperature falls outside the hysteresis (see next fig. 4).
The hysteresis is based on how quickly the heating system can warm up the
room or how quickly the cooling system can lower the temperature in the room
as well as the customer’s sensitivity to temperature levels. The hysteresis should
not be set too low as otherwise the valve drive continually opens and closes. It
should be also not be set too high as the temperature fluctuations in the room
are then fairly considerable.
The correct hysteresis setting avoid continuous switching ON and OFF the
HVAC system around the setpoint threshold.
Next figure shows how the hysteresis works in a 2 step controlling.
Fig. 4: Esample of a 2 Step control with hysteresis
Temp.
+
∆
T
Setpoint
-
∆
T
ON OFF
ON OFF
