Description
Original instructions
About us
Function description
The function block replicates a limited integrator.
The function block has the following properties:
NOTE: This function block performs an internal initialization in the first program cycle after a warm start or cold start (e.g. application download or power cycle) of the PLC program.
Due to this, you have to make sure that the function block is invoked in the first program cycle. In case of inkoving the function block in a later program cycle, the internal initialization will not be performed and the ouputs may deliver wrong values.
WARNING
UNEXPECTED OUTPUT BEHAVIOUR
Make sure that the function block is always invoked in the first program cycle.
Failure to follow these instructions can result in death, serious injury, or equipment damage.
EN and ENO can be configured as additional parameters.
Formula
The transfer function is:
The formula for the output OUT is:
Meaning of the sizes
Variable
Description
Current value of input IN
Value of input IN from the previous cycle
Value of the output OUT from the previous cycle
dt
is the time differential between the current cycle and the previous cycle
Representation in FBD
Representation:
Representation in LD
Representation:
Representation in IL
Representation: 
CAL INTEGRATOR_Instance (IN:=InputVariable, 
    GAIN:=IntegrationGain, OUT_MIN:=LowerOutputLimit, 
    OUT_MAX:=UpperOutputLimit, TR_I:=InitializationInput, 
    TR_S:=InitializationType, OUT=>Output, 
    QMIN=>ReachedLowerLimit, QMAX=>ReachedUpperLimit)
Representation in ST
Representation: 
INTEGRATOR_Instance (IN:=InputVariable, 
    GAIN:=IntegrationGain, OUT_MIN:=LowerOutputLimit, 
    OUT_MAX:=UpperOutputLimit, TR_I:=InitializationInput, 
    TR_S:=InitializationType, OUT=>Output, 
    QMIN=>ReachedLowerLimit, QMAX=>ReachedUpperLimit) ;
Parameter description
Description of input parameters:
Parameter
Data type
Description
IN
REAL
Input variable
GAIN
REAL
Integral gain
OUT_MIN
REAL
Lower limit
OUT_MAX
REAL
Upper limit
TR_I
REAL
Initialization input
TR_S
BOOL
Initialization type
"1" = Operating mode Tracking
"0" = Automatic operating mode
Description of output parameters:
Parameter
Data type
Description
OUT
REAL
Output
QMIN
BOOL
"1" = Output OUT has reached lower limit
QMAX
BOOL
"1" = Output OUT has reached upper limit
Error message
With OUT_MAX < OUT_MIN an error message appears.
NOTE: For a list of all block error codes and values, see Conditioning.