BAC_AC_ExhADmp2P_01_xx

Functional description

The sub template BAC_AC_ExhADmp2P_01_xx is used for control and monitoring of an exhaust air damper with spring return actuator and limit switch monitor. The damper is controlled via a binary output.

	The output variable bOpn outputs the actual state of the damper, if feedback from limit switch SwiOpn is available in the template used. If no end position monitoring is available, it is emulated internally. If the damper is controlled, output bOpn becomes TRUE. As a result, in the start program for a ventilation system BAC_AC_StartT_01, the delay time for starting the fans (SuAFanDlyOn / ExtAFanDlyOn) has to be adjusted to the time it takes for the damper to open.

The template BAC_AC_ExhADmp2P_01_xx is available in different versions.
The damper versions are identified by means of a key. The identification key is derived from the table below.

Options	mechanical priority operation Feedback hand switch	mechanical priority operation Feedback Relay output	Final position Open	Final position Close
Instance	LocSwi	FdbOut	SwiOpn	SwiCls
Data point type	BI	BI	BI	BI
	8	4	2	1
BAC_AC_ExhADmp2P_01_00	0	0	0	0
BAC_AC_ExhADmp2P_01_02	0	0	1	0
BAC_AC_ExhADmp2P_01_03	0	0	1	1
BAC_AC_ExhADmp2P_01_08	1	0	0	0
BAC_AC_ExhADmp2P_01_10	1	0	1	0
BAC_AC_ExhADmp2P_01_11	1	0	1	1
BAC_AC_ExhADmp2P_01_12	1	1	0	0
BAC_AC_ExhADmp2P_01_14	1	1	1	0
BAC_AC_ExhADmp2P_01_15	1	1	1	1

Interface

BAC_AC_ExhADmp2P_01_xx 2:

Plant diagram 01

Plant diagram 02

Block diagram for controlling the damper

Block diagram for monitoring the limit switches

VAR_INPUT

udiPltStp  : UDINT; 
udiOpMod   : UDINT;

udiPltStp: Steps during startup of the air-conditioning plant. See also BAC_AC_StartT_01

udiOpMode: Plant operation mode. See also BAC_AC_OpMod_01

VAR_OUTPUT

bOpn      : BOOL;

bOpn: End position 'open' of the damper has been reached.
If no end position monitoring is available, it is emulated internally. If the damper is controlled, output bOpn becomes TRUE.

VAR CONSTANT

PLT_NUM    : BYTE := 1;

PLT_NUM: all alarms and events of all plant components within a controller are included in a global alarm and event list. The assignment of events and alarms to a plant is defined by the assignment of a PLT_NUM plant number.
The recording and processing of an alarm from an aggregate or a device takes place within the templates by means of the alarm function block FB_BA_Alarm.
The evaluation of the alarms of a plant, e.g. for the generation of a collective message or for plant shutdown in case of relevant faults, takes place within the template BAC_PltAlm_01 by means of the function block FB_BA_AlarmPlt.
The evaluation of different plant events within the templates of a plant, takes place within the template BAC_PltComnMsg_01 by means of the function block FB_BA_ComnMsg.

Important! The assignment and evaluation of the alarms and events of a plant can only be done correctly if all templates of a plant have the same plant number!

The plant number can be assigned in the Project Builder in the parameter menu for the templates or via a column in the Excel import.

Program description

Instance	Type	optional	Task
SwiOpn	FB_BACnetBI1203	X	BI object for connecting the limit switch 'open'
SwiCls	FB_BACnetBI1203	X	BI object for connecting the limit switch 'closed'
OpMod	FB_BACnetMVSetpoint		MV object for manual control of the damper via the MCL or a local operator display
LocSwi	FB_BACnetBI1203	X	BI object for feedback from mechanical priority operation. (manual/emergency operating level)
FdbOut	FB_BACnetBI1203	X	BI object for logging the mechanical priority operation position feedback relay
TiOpn	FB_BACnetAVSetpoint	X	AV object for entering the opening time value
TiCls	FB_BACnetAVSetpoint	X	AV object for entering the closing time value
OpModSfty	FB_BA_MMUX_B04		The multiplexer defines the safety priority of the exhaust air damper depending on the plant operation mode udiOpMod
			udiOpMod			Damper state
			OPMOD_AC_SMEXTTPRG	Smoke extraction program		Open
			OPMOD_AC_SMEXTTSUA	Smoke extraction supply air		Close
			OPMOD_AC_SMEXTTEXHA	Smoke extraction exhaust air		Open
			OPMOD_AC_FIRE	Fire		Close
OpModDst	FB_BA_MMUX_B08		The multiplexer defines the disturbance priority of the exhaust air damper depending on the plant operation mode udiOpMod
			udiOpMod			Damper state
			OPMOD_AC_FORCVENT	Forced ventilation		Open
			OPMOD_AC_EMERG	emergency		Close
			OPMOD_AC_FRST	Frost		Close
			OPMOD_AC_CENTSWIOFF	Central shutdown		Close
			OPMOD_AC_ALM	Fault		Close
OpModPrio RSOpMod	FB_BA_MMUX_B08 RS		The multiplexer defines the plant operation mode udiOpMod. The function RSOpMod is intended to prevent the damper closing immediately if the operation mode changes while the process/fans are running. The start program is designed to shut down and restart the plant when the operation mode changes.
			udiOpMod			Damper state
			OPMOD_AC_MANON	Manual on		Damper does not close until the plant step udiPltStp < PLTSTP_AC_DMP if no longer required
			OPMOD_AC_ON	On		Damper does not close until the plant step udiPltStp < PLTSTP_AC_DMP if no longer required
			OPMOD_AC_NGTCOL	Night cooling		Damper does not close until the plant step udiPltStp < PLTSTP_AC_DMP if no longer required
			OPMOD_AC_COLDWNPRTC	Support operation, cooling protection		Damper does not close until the plant step udiPltStp < PLTSTP_AC_DMP if no longer required
			OPMOD_AC_OVRHTGPRTC	Overheating protection		Damper does not close until the plant step udiPltStp < PLTSTP_AC_DMP if no longer required
BO	FB_BACnetBO1203		BO object for controlling the damper
			Priority:		Enable		Value
			PRIO_SAFETY (1)		see multiplexer OpModSftyudiOpMod		see multiplexer OpModSfty Damper state
			PRIO_DISTURBANCE (3)		see multiplexer OpModDstudiOpMod		see multiplexer OpModDst Damper state
			PRIO_LOCAL (8)		The OR module pools events which enable writing to the priority manual override (local) of the downstream BO object. Events: 1. The MV object has the value OPMOD_MAN_OFF (manual off) 2. The MV object has the value OPMOD_MAN_STP01(manual on)		Open, if OpMod_udiPrVal = OPMOD_MAN_STP01 Otherwise close
			PRIO_PROGRAM (15)		TRUE		If the plant step is udiPltStp >= PLTSTP_AC_DMP, the damper should open
MoveCtrlOpn	FB_BA_SwiMonit	X	Function block, which monitors the 'open' end position of the damper
MoveCtrlCls	FB_BA_SwiMonit	X	Function block, which monitors the 'closed' end position of the damper
AlmFnct	FB_BA_Alarm	x	The AlmFnct function block records the event of the limit position switch monitoring. Actions that are to take place after the limit switch fault is received can be parameterized in the template on the AlmFnct function block.
Alm	FB_BACnetBV1204	x	BV object for displaying the damper fault in the MCL

IO linking

Variables for linking with the terminals

Parameter	Type	optional	Process image
BI_Damper_LimitSwitch_Open	BOOL	X	Input	Digital input - switch damper open - message - actuated/not actuated
BI_Damper_LimitSwitch_Close	BOOL	X	Input	Digital input - switch damper closed - message - actuated/not actuated
BI_Damper_LocalSwitch	BOOL	X	Input	Digital input - switch manual damper - message - manual/automatic
BI_Feedback_Binary_Output	BOOL	X	Input	Digital input - damper switching command - feedback - on/off
BO_Damper	BOOL		Output	Digital output - damper - switching command - on/off

Version history

Version number	Comments
1.0.1	First release