FB_BA_AC_Dmp2P

FB_BA_AC_Dmp2P 1:

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

FB_BA_ActuatorCmd

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.

FB_BA_AC_Dmp2P 2:

The initialization of the template takes place within the method FB_Init.

Block diagram

FB_BA_AC_Dmp2P 3:

Principle diagram 01

The diagram shows the intended use of the template with the plant elements involved.

FB_BA_AC_Dmp2P 4:

Principle diagram 02

The diagram shows the integration of the template within a plant.

FB_BA_AC_Dmp2P 5:

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

FB_BA_AC_Dmp2P 6: 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.

FB_BA_AC_Dmp2P 7: 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.

FB_BA_AC_Dmp2P 8: Inputs/outputs

Name

Type

Description

stAggregate

ST_BA_Aggregate

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.

FB_BA_AC_Dmp2P 9: Inputs CONSTANT

Name

Type

Description

SwiOpn

FB_BA_BI_Raw

Binary input object is used to process the Open limit switch.

SwiCls

FB_BA_BI_Raw

Binary input object is used to process the limit switch Closed.

MonitOpn

FB_BA_FdbCtrlBinary

The template monitors the end position “open” of the damper.

MonitCls

FB_BA_FdbCtrlBinary

The template monitors the end position “Closed” of the damper.

Aggregates

FB_BA_Aggregate

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

FB_BA_PrioSwi_B04

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