PID_FB_DUT

PID processing instruction

This implementation allows you to access the F355_PID instruction via the structure PID_DUT_31.

Parameters

Input

Automatic (BOOL)

FALSE: Manual setting of MV possible

TRUE: Automatic PID controlled MV

Output

PidDut (PID_DUT_31): For a detailed explanation of parameters, please refer to PID_DUT_31

Remarks

The value for MV can be assigned externally either when the program is initialized or when the value of Automatic is FALSE.
In order to achieve maximum resolution and minimum dead time beyond LowerLimit and UpperLimit, these values should, if possible, cover the entire range of 0–10000.

Error flags

sys_bIsOperationErrorHold (turns to TRUE and remains TRUE): if the parameter settings are outside the permissible range
sys_bIsOperationErrorNonHold (turns to TRUE for one scan): if the parameter settings are outside the permissible range

Example

Global variables

In the global variable list you define variables that can be accessed by all POUs in the project.

POU header

All input and output variables used for programming this function have been declared in the POU header. The same POU header is used for all programming languages.

	VAR_EXTERNAL
		Set_Value_SP: INT:=0;
			(*A/D CH0*)
		Process_Value_PV: INT:=0;
			(*A/D CH1*)
		Output_Value_MV: INT:=0;
			(*D/A*)
	END_VAR
	VAR 
		PID_Parameter: PID_DUT;
			(*PID Parameters*)
		PID_Control: PID_FB_DUT;
		@'': @'';
	END_VAR

LD body

BODY
    WORKSPACE
        NETWORK_LIST_TYPE := NWTYPELD ;
        ACTIVE_NETWORK := 0 ;
    END_WORKSPACE
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 4 ;
        NETWORK_BODY
B(B_VARIN,,Set_Value_SP,9,2,11,4,);
B(B_VAROUT,,PID_Parameter.SP,11,2,13,4,);
L(1,0,1,4);
        END_NETWORK_BODY
    END_NET_WORK
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 2 ;
        NETWORK_BODY
B(B_VARIN,,Process_Value_PV,9,0,11,2,);
B(B_VAROUT,,PID_Parameter.PV,11,0,13,2,);
L(1,0,1,2);
        END_NETWORK_BODY
    END_NET_WORK
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 5 ;
        NETWORK_BODY
B(B_FB,PID_FB_DUT!,PID_Control,10,1,18,5,,?BAutomatic?BPidDut?APidDut);
B(B_VARIN,,TRUE,8,2,10,4,);
B(B_VARIN,,PID_Parameter,8,3,10,5,);
L(1,0,1,5);
        END_NETWORK_BODY
    END_NET_WORK
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 4 ;
        NETWORK_BODY
B(B_VARIN,,PID_Parameter.MV,10,2,12,4,);
B(B_VAROUT,,Output_Value_MV,12,2,14,4,);
B(B_COMMENT,,Write manipulated value to the output,3,1,22,2,);
L(1,0,1,4);
        END_NETWORK_BODY
    END_NET_WORK
END_BODY

ST body

PID_Parameter.SP := Set_Value_SP;
PID_Parameter.PV := Process_Value_PV;
PID_Control( Automatic:= TRUE,
        PidDut:= PID_Parameter);
Output_Value_MV := PID_Parameter.MV;