Order No. 2104 ..
i
The hysteresis must be selected in such a way that the start of the measurement range is
not reached or undershot and the end value is not reached or exceeded, as otherwise a
change of state can only occur once and not any more until a reinitialisation.
Setting the hysteresis of the limiting value
The hysteresis of the limiting values for the measured values "CO
2
" and "Humidity" is set by
means of the parameters "Limiting value X" in the parameter node "Limiting value X".
"n limiting values active" is set for the measured value on the parameter page "CO2
measurement" or "humidity measurement". There is a maximum of four (n = 1…4) limiting
values available for the CO
2
measured value, and a maximum of two (n = 1…2) for the humidity
measured value.
o
Enter the appropriate value in the input field "Hysteresis".
The hysteresis is set.
Response of the limiting value object when the limiting value is exceeded and undershot
For the parameter "Activation limiting value X" in the parameter node "Limiting value X" a
direction-dependent setting is made for how the limiting value responds when the set limiting
value is exceeded or undershot. If, for example, "undersh. LV=ON, exceed LV+Hyst.=OFF" is
selected, the limiting value object is then set to "1" if the limiting value is undershot, and the
limiting value object will first be set to "0" when the limiting value plus hysteresis is exceeded.
Figure 15: Activation of limiting value
If for a cycle, "no telegr.", i.e. no telegram is configured, the cyclical transmission of the limiting
value X is also prevented when this function is activated. The cyclical transmission of the
limiting value remains interrupted until the opposite state is reached once again.
Example: Undersh. is configured LV=ON, exceed LV+hyst.=no telegr.
- An ON telegram is sent when the limiting value is undershot. If "Cycl. sending of limiting value
X" is parametrized with '10', then this ON telegram is additionally sent every 100 seconds (10s x
10).
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Software "KNX CO2 sensor"
Functional description
