FB_CTRL_3POINT_EXT

FB_CTRL_3POINT_EXT 1:

The function block provides an extended 3-point element in the functional diagram.

Behavior of the output

fIn := fSetpointValue - fActualValue;

FB_CTRL_3POINT_EXT 2:

VAR_INPUT

VAR_INPUT
    fSetpointValue    : FLOAT;
    fActualValue      : FLOAT;
    fManSyncValue     : FLOAT;
    bSync             : BOOL;
    eMode             : E_CTRL_MODE;
END_VAR

Name	Type	Description
fSetpointValue	FLOAT	Setpoint of the controlled variable
fActualValue	FLOAT	Actual value of the controlled variable
fManSyncValue	FLOAT	Input through which the extended 3-point element can be set to one of the output branches. `\| fManSyncValue \| < 1 → fOut = 0.0 \| fManSyncValue \| >= 1 → fOut = fE * fGain + fOffset`
bSync	BOOL	A rising edge at this input sets the 3-point element to the value "„fManSyncValue".
eMode	E_CTRL_MODE	Input that specifies the operation mode of the function block.

VAR_OUTPUT

VAR_OUTPUT
    fOut        : FLOAT;
    eState      : E_CTRL_STATE;
    eErrorId    : E_CTRL_ERRORCODES;
    bError      : BOOL;
END_VAR

Name	Type	Description
fOut	FLOAT	Output of the extended 3-point element
eState	E_CTRL_STATE	State of the function block
eErrorId	E_CTRL_ERRORCODES	Supplies the error number when the output `bError` is set.
bError	BOOL	Becomes TRUE, as soon as an error occurs.

VAR_IN_OUT

VAR_IN_OUT
    stParams    : ST_CTRL_3POINT_EXT_PARAMS;
END_VAR

Name	Type	Description
stParams	ST_CTRL_ 3POINT_EXT_ PARAMS	Parameter structure of the extended 3-point element

stParams consists of the following elements:

TYPE
ST_CTRL_3POINT_EXT_PARAMS :
STRUCT
    tCtrlCycleTime    : TIME := T#0ms; 
    tTaskCycleTime    : TIME := T#0ms; 
    fOutOff           : FLOAT;     
    fOutOn            : FLOAT;     
    fGain             : FLOAT;    
    fOffset           : FLOAT;     
END_STRUCT
END_TYPE

Name	Type	Description
tCtrlCycleTime	TIME	Cycle time with which the control loop is processed. This must be greater than or equal to the TaskCycleTime. The function block uses this input value to calculate internally whether the state and the output values have to be updated in the current cycle.
tTaskCycle Time	TIME	Cycle time with which the function block is called. If the function block is called in every cycle this corresponds to the task cycle time of the calling task.
fOutOff	FLOAT	If the control deviation falls below this value, the output is switched off (set to zero).
fOutOn	FLOAT	If the control deviation exceeds this value, the output is switched on.
fGain	FLOAT	Gain factor
fOffset	FLOAT	Offset