Damper2P

Damper2P (FB)

FUNCTION_BLOCK Damper2P

Short description

Control of a binary damper actuator with two position feedbacks Typical application: outdoor and exhaust air dampers of an HVAC system

Representation

Interfaces

Inputs

Name	Data type	Value range	Initial value	Function
xY	BOOL			Control signal
xForce	BOOL		FALSE	Forced override after manual override
xAlarmIn	BOOL		FALSE	Actuator fault message
eAOO	HVACTYPES.eManBin	HVACTYPES.eManBin.Auto, HVACTYPES.eManBin.ManOff, HVACTYPES.eManBin.ManOn	HVACTYPES.eManBin.Auto	Operating mode of the manual override - hardware
xOpen	BOOL			Feedback damper open
xClosed	BOOL			Feedback damper closed

Outputs

Name	Data type	Value range	Initial value	Function
xHB	BOOL			Release of damper actuator after manual override
xAB	BOOL			Release of damper actuator before manual override
xAlarmOpen	BOOL			Fault for damper open position
xAlarmClosed	BOOL			Fault for damper closed position
xAlarm	BOOL			Aggregate fault
xAuto	BOOL			Combined message automatic mode

Setpoints / Parameters

Name	Data type	Value range	Initial value	Function
udiControlTime	UDINT	10s … 600s	150s	Reporting delay of the position monitoring
xControl	BOOL		TRUE	Enable position monitoring
xForceOption	BOOL		FALSE	State of the output xHB during forced override
eManModeB	eMANBIN	eMANBIN.Auto, eMANBIN.ManOff, eMANBIN.ManOn	eMANBIN.Auto	Operating mode of the manual override for the digital output xHB

Function description

Automatic output xAB

The release of the damper actuator before manual override xAB is taken unchanged from the enable input xY adopted.

Manual output xHB

The release of the damper actuator after manual override xHB corresponds to the release of the damper actuator before manual override xAB additionally extended by a manual override module and a forced override.

xAB	eManModeB	xForce	xForceOption	xHB	Notes
FALSE	eMANBIN.Auto	FALSE	X	FALSE	Manual override module in automatic
TRUE	eMANBIN.Auto	FALSE	X	TRUE	Manual override module in automatic
X	eMANBIN.ManOff	FALSE	X	FALSE	Manual override module in manual operation Off
X	eMANBIN.ManOn	FALSE	X	TRUE	Manual override module in manual operation On
X	X	TRUE	FALSE	FALSE	Forced override Closed
X	X	TRUE	TRUE	TRUE	Forced override Open

Legend: X = any

Fault for damper open position xAlarmOpen

The fault message for the position at damper opening xAlarmOpen is activated ( xAlarmOpen = TRUE ), if the following conditions are met simultaneously:

1) The release of the position monitoring xControl is enabled ( = TRUE ) 2) As operating mode of the manual override - hardware *eAOO* the automatic mode is selected ( *eAOO* = HVACTYPES.eManBin.Auto ) 3) The states of the release of the damper actuator after manual override *xHB* and the feedback for damper open *xOpen* are continuously different for at least the reporting delay of the position monitoring **udiControlTime** ( ( *xHB* = FALSE and *xOpen* = TRUE ) OR ( *xHB* = TRUE and *xOpen* = FALSE ) ). The fault message for the position at damper opening *xAlarmOpen* is deactivated if at least one of the above conditions is no longer met.

Fault for damper open position xAlarmClosed

The fault message for the position at damper opening xAlarmClosed is activated ( xAlarmClosed = TRUE ), if the following conditions are met simultaneously:

1) The release of the position monitoring xControl is enabled ( = TRUE ) 2) As operating mode of the manual override - hardware *eAOO* the automatic mode is selected ( *eAOO* = HVACTYPES.eManBin.Auto ) 3) The states of the release of the damper actuator after manual override *xHB* and the feedback for damper closed *xClosed* are continuously equal for at least the reporting delay of the position monitoring **udiControlTime** ( ( *xHB* = TRUE and *xOpen* = TRUE ) OR ( *xHB* = FALSE and *xOpen* = FALSE ) ). The fault message for the position at damper opening *xAlarmClosed* is deactivated if at least one of the above conditions is no longer met.

Aggregate fault xAlarm

The aggregate fault xAlarm is activated ( = TRUE ), if at least one of the two faults for the positions of the damper ( xAlarmOpen and xAlarmClosed ) or the input xAlarmIn is active. In all other cases the combined fault is xAlarm is not activated ( = FALSE ).

Combined message automatic mode xAuto

The combined message automatic mode xAuto is activated ( = TRUE ), if the input eAOO contains the value HVACTYPES.eManBin.Auto and the setpoint / parameter eManModeB contains the value eMANBIN.Auto. In all other cases the combined message automatic mode is xAuto is not activated ( = FALSE ).

Forced override xForce

The forced override acts directly on the output xHB. With the parameter xForceOption it is defined which state the output xHB assumes when TRUE at the input xForce takes.

CODESYS

InOut:

Scope	Name	Type	Initial
Input	xY	BOOL
Input	xForce	BOOL	FALSE
Input	xAlarmIn	BOOL	FALSE
Input	eAOO	eManBin	eManBin.Auto
Input	xOpen	BOOL
Input	xClosed	BOOL
Output	xHB	BOOL
Output	xAB	BOOL
Output	xAlarmOpen	BOOL
Output	xAlarmClosed	BOOL
Output	xAlarm	BOOL
Output	xAuto	BOOL
Input Const	udiControlTime	UDINT	200
Input Const	xControl	BOOL	TRUE
Input Const	xForceOption	BOOL	FALSE
Input Const	eManModeB	eMANBIN	eMANBIN.Auto