157/218
Siemens Building Technologies
Basic Documentation RVA63.242, RVA53.242
CE1P2373E
Landis & Staefa Division
Description of OEM settings
26.03.2001
Status
Effect
Locking signal > 5 %
System pump OFF
Locking signal < 0 %
Normal pump operation
Through the generation of the temperature-time integral, it is not only the period of time
that is considered, but also the extent of boiler temperature undershoot. This means
that when the crossing is significant, the pumps will be deactivated earlier.
5.9.2 Impact on modulating loads
Due to the lowering of the setpoint, heat consumption will be reduced. This reduces
considerably the boiler water's heating up time.
•
Mixing valve
Status
Effect
Sperrsignal > 0 %
Flow temperature setpoint will be lowered.
The extent of lowering is dependent on the magnitude
and the period of time of boiler temperature
undershoot.
Locking signal reduced to 0 %
Setpoint according to the normal control condition
Through the generation of the temperature-time integral it is not only the period of time
that is considered, but also the extent of boiler temperature undershoot. This means
that when the undershoot is significant, the setpoint reduction will be greater.
Protective boiler start-up can be interrupted to ensure that, in the event of a burner
fault, for instance, frost protection for the plant will be provided.
In the case of protective boiler start-up and simultaneous frost protection for the plant,
the boiler temperature gradient must turn positive within 15 minutes. Otherwise, the
locking signal will become invalid for at least 15 minutes. On completion of the 15
minutes, protective boiler start-up will become active again as soon as the boiler
temperature gradient turns positive.
Switching point
Setpoint reduction
Supervision