2070
APPX
Appendix 5 PID Control Program Examples
Program examples for PID control when switching modes
The program performs PID operation by switching an automatic mode and a manual mode.
The program conditions are as follows:
In manual mode, the set value (SV) is automatically rewritten to the process value (PV) when PID operation is
performed. Therefore, when the manual mode is returned to the automatic mode, the set value (SV) must be
rewritten to the one used before the mode was switched.
The set value (SV) is rewritten in 10 steps as shown below:
The following formula is used to rewritten the set value (SV).
SV
m
: SV in manual mode
SV
a
: SV in automatic mode
The value obtained with the above operational expression is subtracted from the set value (SV) every second.
The remainder is subtracted in the first subtraction.
Item
Inexact differential
Exact differential
Number of loops that performs PID operation
1
Sampling period
1 second
Device where PID control data are set
Common data
D500, D501
Loop 1 data
D502 to D515
D502 to D511
Device where I/O data are set
Common data
D600 to D609
Loop 1 data
D610 to D630
D610 to D627
Set value (SV) set by external digital
switches and manipulated value (MV)
in manual mode
SV
X30 to X3F
MV in manual mode
X20 to X2F
Device used to start/stop PID control
PID control start command
X0
PID control stop command
X1
Device used to switch the mode
SV set command
X3
MV (in manual mode) set
command
X4
Automatic/manual switch
command
X6 (Off: Automatic mode, On: Manual mode)
Digital value of the R60AD4 and R60DA4
0 to 2000
SM792, SM794
Off
1s
1s
1s
1s
10s
SV in manual mode
Mode change
command
SV in automatic mode
10
-
=
.........
SV
m
SV
a
Subtraction
value
Remainder
Содержание MELSEC iQ-R Series
Страница 1: ...MELSEC iQ R Programming Manual Instructions Standard Functions Function Blocks ...
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Страница 24: ...22 INDEX 2092 INSTRUCTION INDEX 2093 REVISIONS 2104 WARRANTY 2105 TRADEMARKS 2106 ...
Страница 34: ...32 MEMO ...
Страница 35: ...33 PART 1 PART 1 OVERVIEW This part consists of the following chapter 1 OVERVIEW ...
Страница 68: ...66 1 OVERVIEW 1 5 Precautions on Programming MEMO ...
Страница 204: ...202 5 SEQUENCE INSTRUCTIONS 5 3 Output Instructions Operation error There is no operation error ...
Страница 470: ...468 6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions Operation error There is no operation error ...
Страница 472: ...470 6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions Operation error There is no operation error ...
Страница 479: ...6 BASIC INSTRUCTIONS 6 6 Data Conversion Instructions 477 6 Operation error There is no operation error ...
Страница 504: ...502 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 518: ...516 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 520: ...518 6 BASIC INSTRUCTIONS 6 7 Data Transfer Instructions Operation error There is no operation error ...
Страница 754: ...752 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 756: ...754 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 758: ...756 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 760: ...758 7 APPLICATION INSTRUCTIONS 7 9 Real Number Instructions Operation error There is no operation error ...
Страница 895: ...7 APPLICATION INSTRUCTIONS 7 16 Ramp Signal Instruction 893 7 Operation error There is no operation error ...
Страница 917: ...7 APPLICATION INSTRUCTIONS 7 20 Data Processing Instructions 915 7 Operation error There is no operation error ...
Страница 919: ...7 APPLICATION INSTRUCTIONS 7 20 Data Processing Instructions 917 7 Operation error There is no operation error ...
Страница 1415: ...13 SFC PROGRAM INSTRUCTIONS 13 1 SFC Control Instructions 1413 13 Operation error There is no operation error ...
Страница 1448: ...1446 14 REDUNDANT SYSTEM INSTRUCTIONS 14 2 Disabling Enabling System Switching MEMO ...
Страница 1795: ...25 TYPE CONVERSION FUNCTIONS 25 1 Converting BOOL to WORD 1793 25 Operation error There is no operation error ...
Страница 1805: ...25 TYPE CONVERSION FUNCTIONS 25 10 Converting WORD to DINT 1803 25 Operation error There is no operation error ...
Страница 1819: ...25 TYPE CONVERSION FUNCTIONS 25 21 Converting INT to DWORD 1817 25 Operation error There is no operation error ...
Страница 1950: ...1948 32 STRING FUNCTIONS 32 2 Extracting String Data From the Left Right Operation error There is no operation error ...
Страница 1972: ...1970 33 TIME DATA TYPE FUNCTIONS 33 4 Division MEMO ...
Страница 2067: ...APPX Appendix 5 PID Control Program Examples 2065 A 252 Set PID control data for loop 2 ...
Страница 2082: ...2080 APPX Appendix 6 Process Control Program Examples 129 Set the default value of the loop tag ...
Страница 2093: ...APPX Appendix 7 List of Loop Tag Memory Areas Used by Process Control Instructions 2091 A MEMO ...
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