Siemens RVA63.242 - Release Integral of Burner Stage 2; Temperature-Time Integral

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Siemens Building Technologies Basic Documentation RVA63.242, RVA53.242 CE1P2373E
Landis & Staefa Division Description of OEM settings 26.03.2001
5.5 Release integral of burner stage 2
Optimum switching on of burner stage 2.
Adjustment of heat deficit for releasing burner stage 2.
Setting range Unit Factory setting
0...500 °C (K) min 50
The setting will change the switch-on point for burner stage 2.
Entry:
Increase: Burner stage 2 will be released when the heat deficit is greater
Decrease: Burner stage 2 will be released when the heat deficit is smaller
If, with burner stage 1, the boiler temperature falls below the switch-on setpoint (TKw -
SDK/2) by the amount of the release integral set here, the controller will release the
second burner stage.
During the time burner stage 2 is released, the controller will activate and deactivate
burner stage 2 according to the switching differential.
5.5.1 Temperature-time integral
The temperature-time integral is a continuous summation of the temperature differential
over time. In this case, the decisive criterion is the difference by which the boiler
temperature falls below the burner’s switch-on setpoint (TKw-SDK/2-TKx).
Through the generation of the temperature-time integral it is not only the period of time
that is considered, but also the extent of the undershoot. This means that when the
crossing is significant, burner stage 2 will be released earlier.
When the release integral (area "a" in the diagram below) has reached the value set
(point in time tF), burner stage 2 will be released.
50
48
52
TKx
2371Z32
°C
44
46
t
TKw+SDK/2
a
TKw
TKw-SDK/2
tF
a Release limit
TKw Boiler temperature setpoint
TKx Actual value of the boiler temperature
SDK Switching differential of the boiler
t Time
tF Time to release
Benefit
Description
Setting
Effect
Burner stage 2
Note
Switching point
Example