FB_BA_AC_Dmp2P
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The aggregate template represents the control of a two-point damper with integrated monitoring of both end positions.
Typical applications of the template are the fresh air and exhaust air dampers of an air conditioning system.
An essential component of the damper control is the template
The damper is integrated into the system control program of the ventilation system using the function block Aggregate.
Each template is available in 2 different configurations regarding the connection to the I/O process level, see I/O mapping. This documentation refers to the RAW variant.
![]() | The initialization of the template takes place within the method FB_Init. |
Block diagram
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Principle diagram 01
The diagram shows the intended use of the template with the plant elements involved.
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Principle diagram 02
The diagram shows the integration of the template within a plant.
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Syntax
FUNCTION_BLOCK FB_BA_AC_Dmp2P EXTENDS FB_BA_ActuatorCmd
VAR_INPUT
bFan : BOOL;
END_VAR
VAR_OUTPUT
bSwiOpn : BOOL;
bSwiCls : BOOL;
END_VAR
VAR_IN_OUT
stAggregate : ST_BA_Aggregate;
END_VAR
VAR_INPUT CONSTANT
SwiOpn : FB_BA_BI_Raw;
SwiCls : FB_BA_BI_Raw;
MonitOpen : FB_BA_FdbBinary;
MonitClose : FB_BA_FdbBinary;
Aggregate : FB_BA_Aggregate;
END_VAR
VAR
PrioSwiFan : FB_BA_PrioSwi_B04;
END_VAR
Inputs
Name | Type | Description |
---|---|---|
bFan | BOOL | The "Fan On" input signal is used within a ventilation and air conditioning system to protect the connected damper. As long as the input signal "Fan On" is TRUE, the priority "Critical" is enabled on the priority switch PrioSwiFan within the template and the damper is switched on. |
Outputs
Name | Type | Description |
---|---|---|
bSwiOpn | BOOL | End position "open" of the damper has been reached. |
bSwiCls | BOOL | End position "closed" of the damper has been reached. |
Inputs/outputs
Name | Type | Description |
---|---|---|
stAggregate | Bidirectional aggregate structure via which the enables and switching values are transmitted to the evaluation function block of the step sequence control Aggregate. The aggregate structure transmits the recorded feedback signals up and down to the central plant control. |
Inputs CONSTANT
Name | Type | Description |
---|---|---|
SwiOpn | Binary input object is used to process the Open limit switch. | |
SwiCls | Binary input object is used to process the limit switch Closed. | |
MonitOpn | The template monitors the end position “open” of the damper. | |
MonitCls | The template monitors the end position “Closed” of the damper. | |
Aggregates | The aggregate function block represents a receive block of a step sequence controller. Within the function block, the aggregate structure stAggregate is evaluated and integrated into the template using the inputs and outputs. |
Variables
Name | Type | Description |
---|---|---|
PrioSwiFan | The priority switch PrioSwiFan uses the aggregate function block Aggregate and the input variable bFan to determine the enable conditions and switch-on values for the priority critical of the damper. |
Requirements
Development environment | Necessary function |
---|---|
TwinCAT from v3.1.4024.56 | TF8040 | TwinCAT Building Automation from V5.8.0.0 |