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Siemens Building Technologies
Basic Dokumentation RVA63.280, RVA53.280
CE1P2374E
Landis & Staefa Division
19.04.2001
3.5
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.
3.5.1
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
23
71
Z
3
2
°C
44
46
t
TKw+SDK/2
a
TKw
TKw-SDK/2
tF
a
release limit
TKw
Boiler temperature setpoint
TKx
Actual value of boiler temperature
SDK
Switching differential of boiler
t
Time
tF
Time to release
Benefit
Description
Setting
Effect
Burner stage 2
Note
Switching point
Example