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Siemens Building Technologies
Basic Documentation RVL471
CE1P2524E
HVAC Products
11 Function block "3-position actuator heating circuit"
23.10.2002
11 Function block "3-position actuator
heating circuit"
This function block provides 3-position control of the heating circuit. Depending on the
plant type, it acts as follows:
•
Weather-compensated, on the mixing valve of a space heating system (plant type 1–x)
•
Weather-compensated, on the valve in the primary return of a space heating system
with a district heat connection (plant type 3–x)
•
Demand-compensated, on the mixing valve of a main flow (plant type 4–x)
•
Demand-compensated, on the valve in the primary return of a main flow with district
heat connection (plant type 6–x)
11.1 Operating lines
Line
Function, parameter
Unit
Factory
setting
Range
81
Maximum limitation of flow temperature
°C
---
--- / 0...140
82
Minimum limitation of flow temperature
°C
---
--- / 0...140
83
Maximum rate of flow temperature increase
°C
---
--- / 1...600
84
Flow temperature boost mixing valve / heat exchanger
°C
10
0...50
85
Actuator running time
s
120
30...873
86
P-band of control (Xp)
°C
32.0
1...100
87
Integral action time of control (Tn)
s
120
30...873
11.2 Limitations
11.2.1
Flow temperature limitations
The following settings can be made:
•
Maximum limitation of the flow temperature. At the limit value, the heating curve runs
horizontally. This means that the flow temperature setpoint cannot exceed the maxi-
mum value
•
Minimum limitation of the flow temperature: At the limit value, the heating curve runs
horizontally. This means that the flow temperature setpoint cannot fall below the mini-
mum value (exception: with locking signals)
If the setpoint is limited, the display shows:
= for maximum limitation
= for minimum limitation
Both limitations can be deactivated (setting ---).
Minimum limitation is also active during storage tank charging, depending on the kind of
priority.
With plant types 3–1 and 3-3, where maximum limitation is not active during storage
tank charging.
Settings
Impact on d.h.w. heating
