Impact On Modulating Loads - Siemens RVA63.280 Basic Documentation

Switching point
Setpoint reduction
Supervision
Siemens Building Technologies
Landis & Staefa Division
System pump
Status
Locking signal > 5 %
Locking signal < 0 %
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.
3.9.2

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
Locking signal > 0%
Locking signal reduced to
0 %
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.
Basic Dokumentation RVA63.280, RVA53.280
Effect
System pump OFF
Normal pump operation
Effect
Flow temperature setpoint will be lowered.
The extent of lowering is dependent on the magnitude and
the period of time of boiler temperature undershoot.
Setpoint according to the normal control condition
139/184
CE1P2374E
19.04.2001