Damper2P

Damper2P (FB)

FUNCTION_BLOCK Damper2P

Short description

Control of a binary damper actuator with two position feedbacks Typical application: supply and exhaust 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 manual override - hardware
xOpen	BOOL			Feedback damper open
xClosed	BOOL			Feedback damper closed

Outputs

Name	Data type	Value range	Initial value	Function
xHB	BOOL			Actuator enable after manual override
xAB	BOOL			Actuator enable before manual override
xAlarmOpen	BOOL			Fault position damper open
xAlarmClosed	BOOL			Fault position damper closed
xAlarm	BOOL			Aggregate fault
xAuto	BOOL			Collective automatic-mode message

Setpoints / parameters

Name	Data type	Value range	Initial value	Function
udiControlTime	UDINT	10s … 600s	150s	Reporting delay of position monitoring
xControl	BOOL		TRUE	Enablement of the 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 actuator enable before manual override xAB is passed unchanged from the enable input xY adopted.

Manual output xHB

The actuator enable after manual override xHB corresponds to the actuator enable 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 Off
X	X	TRUE	TRUE	TRUE	Forced override On

Legend: X = any

Fault position damper open xAlarmOpen

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

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

Fault position damper open xAlarmClosed

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

1) The enable of position monitoring xControl is enabled (= TRUE) 2) As operating mode of the manual override hardware *eAOO*, automatic operation is selected (*eAOO* = HVACTYPES.eManBin.Auto) 3) The states of the actuator enable after manual override *xHB* and the feedback for the damper closing *xClosed* are continuously equal for at least the duration of the position monitoring reporting delay **udiControlTime** ((*xHB* = TRUE and *xOpen* = TRUE) OR (*xHB* = FALSE and *xOpen* = FALSE)). The fault message for the position when the damper opens *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 flap positions (xAlarmOpen and xAlarmClosed) or the input xAlarmIn is active. In all other cases the collective fault is xAlarm is not activated (= FALSE).

Collective automatic-mode message xAuto

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

Forced override xForce

The forced override acts directly on the output xHB. The parameter xForceOption determines which state the output xHB assumes when TRUE at the input xForce .

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