Fan1Speed

Fan1Speed (FB)

FUNCTION_BLOCK Fan1Speed

Short description

Control of a single-stage fan Additional functions: air shortage monitoring, operation monitoring, repair switch, manual override, status indication Typical application: control of a room exhaust fan

Representation

Interfaces

Inputs

Name	Data type	Value range	Initial value	Function
xEn	BOOL			Fan request
xForce	BOOL		FALSE	Forced override after manual override
xFb	BOOL			Fan operating indication
xPFb	BOOL			Air shortage situation indication
xMSwitch	BOOL		TRUE	Repair switch indication
xAlarmIn	BOOL			Fan fault indication
eAOO	HVACTYPES.eManBin	HVACTYPES.eManBin.Auto, HVACTYPES.eManBin.ManOff, HVACTYPES.eManBin.ManOn	HVACTYPES.eManBin.Auto	Operating mode of manual override - hardware
xQuit	BOOL		FALSE	Reset of fault indications (operation monitoring, air shortage monitoring)

Outputs

Name	Data type	Value range	Initial value	Function
xHB	BOOL			Enable - fan after manual override
xAB	BOOL			Enable - fan before manual override
xAlarmFb	BOOL			Operation monitoring fault indication
xAlarmPFb	BOOL			Air shortage monitoring fault indication
dtLastFb	DATE_AND_TIME			Date/time of the fan’s last operation
udiOperatingHours	UDINT			Operating hours of the circulation pump
udiCountFb	UDINT			Number of switch-ons of the circulation pump
xAlarm	BOOL			General fault indication
xAuto	BOOL			Collective automatic mode message

Setpoints / parameters

Name	Data type	Value range	Initial value	Function
udiPFbControlTime	UDINT	1 to 3600 s	60s	Reporting delay of air shortage monitoring
xPFbControl	BOOL		TRUE	Enable air shortage monitoring
xAlarmControl	BOOL		TRUE	Influence of xAlarm on xAB
udiFbControlTime	UDINT	0 … 300s	60s	Reporting delay of operation monitoring
xFbControl	BOOL		TRUE	Enable/disable operation monitoring
xForceOption	BOOL		FALSE	State of the output xHB under 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

General

This function block controls a single-stage fan. Essentially, the following function blocks are used:

AirShortage

ManBin

OperatingHours

Enable - fan before manual override xAB

The enable - fan before manual override xAB is influenced by the fan request xEn, the general fault indication xAlarm, the repair switch indication xMSwitch, the parameter xAlarmControl and the air shortage monitoring. The enable - fan before manual override xAB is active (= TRUE) if the following states occur simultaneously: Case 1: &#xNAN;xEn = TRUE (request active) &#xNAN;xMSwitch = TRUE (motor protection switch not tripped) xAlarmControl = FALSE (general fault indication not considered) Case 2: &#xNAN;xEn = TRUE (request active) &#xNAN;xAlarm = FALSE (general fault indication not active) &#xNAN;xMSwitch = TRUE (motor protection switch not tripped) xAlarmControl = TRUE (general fault indication considered) In all other situations, the enable - fan before manual override xAB is not active ( = FALSE ).

Enable - fan after manual override xHB

The enable - fan before manual override xHB corresponds to the enable - fan before manual override xAB, additionally extended by a manual override module and by 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.ManOn	FALSE	X	TRUE	Manual override module in manual operation On
X	eMANBIN.ManOff	FALSE	X	FALSE	Manual override module in manual operation Off
X	X	TRUE	FALSE	FALSE	Forced override Off
X	X	TRUE	TRUE	TRUE	Forced override On

Legend: X = don't care

Repair switch indication xMSwitch

xMSwitch = TRUE: repair switch not tripped (normal condition) &#xNAN;xMSwitch = FALSE: repair switch tripped (fault condition)

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 at TRUE on the input xForce .

Operating hours and switching operations

The number of operating hours and the switching operations are recorded (= counting process active) if the fan operating indication xFb is active and at the same time the general fault indication xAlarm is not active (= FALSE). The results are available at the counter outputs udiOperatingHours and udiCountFb available.

Write access to the counters

Via the path 'InstanceName._OperatingHours.udiOperatingHours' or 'InstanceName._OperatingHours.udiCountFb' write access to both counters is possible.

Date/time of the fan’s last operation dtLastFb

At the output dtLastFb the current date/time is available during the counting process. At the output dtLastFb the date/time at the end of the last counting process is available outside the counting process. At the output dtLastFb before the first counting process, the initialization value DT#1970-1-1-0.0.0 is output.

Operating monitoring

Operation monitoring can be enabled/disabled via the setpoint/parameter xFbControl enabled (= TRUE) or disabled (= FALSE). When monitoring is disabled, the operation monitoring fault indication xAlarmFb is always disabled (= FALSE). When monitoring is enabled, the operation monitoring fault indication xAlarmFb is activated (= TRUE) if simultaneously during a minimum time period udiFbControlTime the following states are present: &#xNAN;xHB and xFb = unequal (enable state and operating state do not match) &#xNAN;eAOO = HVACTYPES.eManBin.Auto (manual override hardware in automatic) &#xNAN;xFbControl = TRUE (operation monitoring is enabled) The operation monitoring fault indication xAlarmFb is reset (= FALSE) if at least one of the following conditions is met: &#xNAN;eAOO = HVACTYPES.eManBin.Auto (switching back to automatic operation of the manual override hardware) &#xNAN;xQuit = TRUE (fault reset is active) &#xNAN;xFbControl = FALSE (operation monitoring disabled)

Air shortage monitoring

It is used to detect an air shortage situation by evaluating the signals at the inputs air shortage situation indication xPFb and the fan operating indication xFb. Air shortage monitoring can be enabled/disabled via the setpoint/parameter xPFbControl enabled (= TRUE) or disabled (= FALSE). In the disabled state, the output - fault indication xAlarmPFb is not activated (= FALSE). The output - fault indication xAlarmPFb is activated ( xAlarmPFb = TRUE) if conditions 1 and 2 below are simultaneously met. Condition 1: The input for the differential pressure switch xPFb is in the state FALSE (= air shortage situation) continuously for at least the waiting time udiPFbControlTime . Condition 2: The operating indication for the fan xFb is in the state FALSE (= air shortage situation) continuously for at least the waiting time udiPFControlTime is continuously in the state TRUE (= fan in operation). The output - fault indication xAlarmPFb is deactivated in the following cases ( xAlarmPFb = FALSE): Case 1: Conditions 1 and/or 2 are not met and the fault reset xQuit is active (= TRUE).

General fault indication xAlarm

The general fault indication is activated (= TRUE) if at least one of the conditions described below is met. &#xNAN;xAlarmIn = TRUE (fan fault indication is active) &#xNAN;xAlarmFB = TRUE (fault from operation monitoring) &#xNAN;xAlarmPFb = TRUE (fault from air shortage monitoring) &#xNAN;xMSwitch = FALSE (repair switch was tripped) In all other cases, the general fault is not active (= 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 contains the value eMANBIN.Auto. In all other cases the collective automatic mode message xAuto is not activated ( = FALSE ).

CODESYS

InOut:

Scope	Name	Type	Initial
Input	xEn	BOOL
Input	xForce	BOOL	FALSE
Input	xFb	BOOL
Input	xPFb	BOOL
Input	xMSwitch	BOOL	TRUE
Input	xAlarmIn	BOOL
Input	eAOO	eManBin	eManBin.Auto
Input	xQuit	BOOL	FALSE
Output	xHB	BOOL
Output	xAB	BOOL
Output	xAlarmFb	BOOL
Output	xAlarmPFb	BOOL
Output	dtLastFb	DT
Output	udiOperatingHours	UDINT
Output	udiCountFb	UDINT
Output	xAlarm	BOOL
Output	xAuto	BOOL
Input Const	udiPFbControlTime	UDINT	60
Input Const	xPFbControl	BOOL	TRUE
Input Const	xAlarmControl	BOOL	TRUE
Input Const	udiFbControlTime	UDINT	60
Input Const	xFbControl	BOOL	TRUE
Input Const	xForceOption	BOOL	FALSE
Input Const	eManModeB	eMANBIN	eMANBIN.Auto

Methods:

mQuit

mResetOperatingHours

Structure:

• mQuit (Method)

• mResetOperatingHours (Method)