FB_CTRL_HYSTERESIS

FB_CTRL_HYSTERESIS 1:

The function block provides a hysteresis transfer element in a functional diagram.

Transfer function

FB_CTRL_HYSTERESIS 2:

VAR_INPUT

VAR_INPUT
    fIn              : FLOAT;
    bManSyncValue    : BOOL;
    bSync            : BOOL;
    eMode            : E_CTRL_MODE;
END_VAR

Name	Type	Description
fIn	FLOAT	Input of the hysteresis element
bManSync Value	BOOL	Input through which the hysteresis element can be set to one of the two junctions.
bSync	BOOL	A rising edge at this input sets the hysteresis element to the value "fManSyncValue".
eMode	E_CTRL_MODE	Input that specifies the operation mode of the function block.

VAR_OUTPUT

VAR_OUTPUT
    bOut        : BOOL;
    eState      : E_CTRL_STATE;
    eErrorId    : E_CTRL_ERRORCODES;
    bError      : BOOL;
END_VAR

Name	Type	Description
bOut	BOOL	Output of the hysteresis element
eState	E_CTRL_STATE	State of the function block
eErrorId	E_CTRL_ERROR CODES	Supplies the error number when the output `bError` is set.
bError	BOOL	Becomes TRUE as soon as an error situation occurs.

VAR_IN_OUT

VAR_IN_OUT
    stParams    : ST_CTRL_HYSTERESIS_PARAMS;
END_VAR

Name	Type	Description
stParams	ST_CTRL_ HYSTERESIS_ PARAMS	Parameter structure of the hysteresis element

stParams consists of the following elements:

TYPE
ST_CTRL_HYSTERESIS_PARAMS :
STRUCT
    tCtrlCycleTime      : TIME := T#0ms;
    tTaskCycleTime      : TIME := T#0ms;
    fHysteresisRange    : 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.
tTaskCycleTime	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.
fHysteresis Range	FLOAT	Hysteresis range, see diagram above.