Room Temperature Influence; Heating Curve; Purpose; Basic Setting - Siemens RVL470 Basic Documentation

8.5.2. Room temperature influence

8.6. Heating curve

8.6.1. Purpose

8.6.2. Basic setting

Siemens Building Technologies
Landis & Staefa Division
The room temperature is included in the control process, in which case a room tem-
perature sensor is required (sensor or room unit).
The gain factor for the room temperature influence can be adjusted. This indicates to
what extent deviations of the actual room temperature from the setpoint have an impact
on flow temperature control:
0 = room temperature deviations have no impact on the generation of the setpoint
20 = room temperature deviations have a maximum impact on the generation of the
setpoint
The reduction of the room temperature setpoint ∆T
lowing formula:
VF
∆T
[K] = –––––
( T
Rw *
2
T
Rw
T
Rw
The change of the flow temperature setpoint resulting from the change of the room tem-
perature setpoint is calculated as follows:
∆T [K] = ∆T
( 1 + s )
Vw Rw *
where:
s Heating curve slope
T Room temperature setpoint
Rw
∆T
Change of room temperature setpoint
Rw
-∆T Reduction of room temperature setpoint
Rw
+∆T Increase of room temperature setpoint
Rw
T Actual value of room temperature
Rx
∆T
Room temperature deviation (T
R
∆T
Change of flow temperature setpoint
Vw
VF Gain factor
With the space heating systems (plant types 1, 2 and 3), flow temperature control is
always weather-compensated. Assignment of the flow temperature setpoint to the pre-
vailing outside temperature is made via the heating curve.
The basic setting of the heating curve is made with the little bar or via two operating
lines (also refer to section "19.1.2. Analog operating elements").
The following settings are required:
•
The flow temperature setpoint at –5 °C outside temperature
•
The flow temperature setpoint at +15 °C outside temperature
The basic setting during commissioning is made according to the planning documenta-
tion or in agreement with local practices.
Basic Documentation RVL470
Function block "Space heating"
Rw
– T )
Rw Rx
T )
–
Rw Rx
is calculated according to the fol-
T
R
CE1P2522E / 30.03.2000
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