Mitsubishi Electric MELSEC Q Series Owner's manual

MELSEC-Q/L/QnA Programming Manual
(PID Control Instructions)

1
SAFETY PRECAUTIONS
(Read these precautions before using this product.)
Before using this product, please read this manual and the relevant manuals carefully and pay full attention to safety to handle
the product correctly.
The precautions given in this manual are concerned with this product only. For the safety precautions of the programmable
controller system, refer to the user's manual for the CPU module used.
In this manual, the safety precautions are classified into two levels: " WARNING" and " CAUTION".
Under some circumstances, failure to observe the precautions given under " CAUTION" may lead to serious
consequences.
Observe the precautions of both levels because they are important for personal and system safety.
Make sure that the end users read this manual and then keep the manual in a safe place for future reference.
[Design Precautions]
WARNING
●Configure safety circuits external to the programmable controller to ensure that the entire system
operates safely even when a fault occurs in the external power supply or the programmable controller.
Failure to do so may result in an accident due to an incorrect output or malfunction.
(1) Emergency stop circuits, protection circuits, and protective interlock circuits for conflicting
operations (such as forward/reverse rotations or upper/lower limit positioning) must be configured
external to the programmable controller.
(2) When the programmable controller detects an abnormal condition, it stops the operation and all
outputs are:
• Turned off if the overcurrent or overvoltage protection of the power supply module is activated.
• Held or turned off according to the parameter setting if the self-diagnostic function of the CPU
module detects an error such as a watchdog timer error.
(3) All outputs may be turned on if an error occurs in a part, such as an I/O control part, where the
CPU module cannot detect any error. To ensure safety operation in such a case, provide a safety
mechanism or a fail-safe circuit external to the programmable controller. For a fail-safe circuit
example, refer to "General Safety Requirements" in the MELSEC-L CPU Module User's Manual
(Hardware Design, Maintenance and Inspection).
●Configure a circuit so that the programmable controller is turned on first and then the external power
supply. If the external power supply is turned on first, an accident may occur due to an incorrect output
or malfunction.
WARNING Indicates that incorrect handling may cause hazardous conditions, resulting in
death or severe injury.
CAUTION Indicates that incorrect handling may cause hazardous conditions, resulting in
minor or moderate injury or property damage.

2
[Design Precautions]
[Startup and Maintenance Precautions]
WARNING
●When connecting a peripheral with the CPU module or connecting an external device, such as a
personal computer, with an intelligent function module to modify data of a running programmable
controller, configure an interlock circuit in the program to ensure that the entire system will always
operate safely. For other forms of control (such as program modification or operating status change)
of a running programmable controller, read the relevant manuals carefully and ensure that the
operation is safe before proceeding. Especially, when a remote programmable controller is controlled
by an external device, immediate action cannot be taken if a problem occurs in the programmable
controller due to a communication failure. To prevent this, configure an interlock circuit in the program,
and determine corrective actions to be taken between the external device and CPU module in case of
a communication failure.
CAUTION
●Before performing online operations (especially, program modification, forced output, and operating
status change) for the running CPU module from the peripheral connected, read relevant manuals
carefully and ensure the safety. Improper operation may damage machines or cause accidents.

3
CONDITIONS OF USE FOR THE PRODUCT
(1) Mitsubishi programmable controller ("the PRODUCT") shall be used in conditions;
i) where any problem, fault or failure occurring in the PRODUCT, if any, shall not lead to any major or serious accident;
and
ii) where the backup and fail-safe function are systematically or automatically provided outside of the PRODUCT for the
case of any problem, fault or failure occurring in the PRODUCT.
(2) The PRODUCT has been designed and manufactured for the purpose of being used in general industries.
MITSUBISHI SHALL HAVE NO RESPONSIBILITY OR LIABILITY (INCLUDING, BUT NOT LIMITED TO ANY AND ALL
RESPONSIBILITY OR LIABILITY BASED ON CONTRACT, WARRANTY, TORT, PRODUCT LIABILITY) FOR ANY
INJURY OR DEATH TO PERSONS OR LOSS OR DAMAGE TO PROPERTY CAUSED BY the PRODUCT THAT ARE
OPERATED OR USED IN APPLICATION NOT INTENDED OR EXCLUDED BY INSTRUCTIONS, PRECAUTIONS, OR
WARNING CONTAINED IN MITSUBISHI'S USER, INSTRUCTION AND/OR SAFETY MANUALS, TECHNICAL
BULLETINS AND GUIDELINES FOR the PRODUCT.
("Prohibited Application")
Prohibited Applications include, but not limited to, the use of the PRODUCT in;
• Nuclear Power Plants and any other power plants operated by Power companies, and/or any other cases in which the
public could be affected if any problem or fault occurs in the PRODUCT.
• Railway companies or Public service purposes, and/or any other cases in which establishment of a special quality
assurance system is required by the Purchaser or End User.
• Aircraft or Aerospace, Medical applications, Train equipment, transport equipment such as Elevator and Escalator,
Incineration and Fuel devices, Vehicles, Manned transportation, Equipment for Recreation and Amusement, and
Safety devices, handling of Nuclear or Hazardous Materials or Chemicals, Mining and Drilling, and/or other
applications where there is a significant risk of injury to the public or property.
Notwithstanding the above, restrictions Mitsubishi may in its sole discretion, authorize use of the PRODUCT in one or
more of the Prohibited Applications, provided that the usage of the PRODUCT is limited only for the specific
applications agreed to by Mitsubishi and provided further that no special quality assurance or fail-safe, redundant or
other safety features which exceed the general specifications of the PRODUCTs are required. For details, please
contact the Mitsubishi representative in your region.

4
CONTENTS
SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
CONDITIONS OF USE FOR THE PRODUCT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
MANUALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
RELEVANT MANUALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
GENERIC TERMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
CHAPTER 1 GENERAL DESCRIPTION 10
1.1 PID Processing Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
CHAPTER 2 SYSTEM CONFIGURATION FOR PID CONTROL 12
2.1 Applicable CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
CHAPTER 3 PID CONTROL SPECIFICATIONS 14
3.1 PID Control by incomplete derivative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Performance specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
PID operation block diagram and operation expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
PID control instruction list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2 PID Control by Complete Derivative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Performance specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
PID operation block diagram and operation expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
PID control instruction list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
CHAPTER 4 FUNCTIONS OF PID CONTROL 25
4.1 Outline of PID Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2 Functions of PID Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Operation method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Forward operation and reverse operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Proportional operation (P operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Integral operation (I operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Derivative operation (D operation). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
PID operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.3 Other Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Bumpless changeover function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
MV upper/lower limit control function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Function for transfer to the SV storage device for the PV in manual mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Changing the PID control data or input/output data setting range (for QCPU and LCPU) . . . . . . . . . . . . . . . . . 33
CHAPTER 5 PID CONTROL PROCEDURE 34
5.1 PID Control Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Number of loops to be used and the number of loops to be executed in a single scan . . . . . . . . . . . . . . . . . . . 49
Sampling cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.2 I/O Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
CHAPTER 6 PID CONTROL INSTRUCTIONS 56
CHAPTER 7 HOW TO READ EXPLANATIONS FOR INSTRUCTIONS 58

5
CONTENTS
CHAPTER 8 INCOMPLETE DERIVATIVE PID CONTROL INSTRUCTIONS AND
PROGRAM EXAMPLES 60
8.1 PID Control Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
PID control data settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
PID operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Operation stop/start of designated loop no.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Parameter change at designated loop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
8.2 PID Control Program Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
System configuration for program examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Program example for automatic mode PID control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Program example for changing the PID control mode between automatic and manual . . . . . . . . . . . . . . . . . . . 69
CHAPTER 9 COMPLETE DERIVATIVE PID CONTROL INSTRUCTIONS AND
PROGRAM EXAMPLES 72
9.1 PID Control Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
PID control data settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
PID control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Monitoring PID control status (QnACPU only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Operation stop/start of designated loop no.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Parameter change at designated loop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
9.2 PID Control Program Examples (for QCPU and LCPU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
System configuration for program examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Program example for automatic mode PID control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Program example for changing the PID control mode between automatic and manual . . . . . . . . . . . . . . . . . . . 84
9.3 PID Control Program Examples (QnACPU only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
System configuration for program examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Program example for automatic mode PID control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Program example for changing the PID control mode between automatic and manual . . . . . . . . . . . . . . . . . . . 92
APPENDICES 96
Appendix 1 Processing Time List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Appendix 2 Anti-Reset Windup Measure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
INDEX 101
INSTRUCTION INDEX 103
REVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

6
MANUALS
The manuals related to this product are listed below.
In necessary, order them by quoting the details in the tables below.
RELEVANT MANUALS
Before reading this manual, refer to the user's manual of the used CPU module or the QnACPU Programming Manual
(Fundamentals), and confirm which programs, I/O processing, and devices can be used with the used CPU module.
Manual name Manual number
(Model Code)
QnUCPU User's Manual (Function Explanation, Program Fundamentals)
Describes the functions, programming procedures, devices, etc. necessary to create programs. (Sold separately)
SH-080807ENG
(13JZ27)
Qn(H)/QnPH/QnPRHCPU Users Manual(Function Explanation, Program Fundamentals)
Describes the functions, programming procedures, devices, etc. necessary to create programs. (Sold separately)
SH-080808ENG
(13JZ28)
MELSEC-L CPU Module User's Manual (Function Explanation, Program Fundamentals)
Describes the functions, programming procedures, devices, etc. necessary to create programs.
SH-080889ENG
(13JZ35)
QnACPU Programming Manual (Fundamentals)
Describes how to create programs, the names of devices, parameters, and types of program. (Sold separately)
IB-66614
(13JF46)
MELSEC-Q/L Programming Manual (Common Instructions)
Describes how to use sequence instructions, basic instructions, and application instructions. (Sold separately)
SH-080809ENG
(13JW10)
QnACPU Programming Manual (Common Instructions)
Describes how to use sequence instructions, basic instructions, and application instructions. (Sold separately)
SH-080810ENG
(13JW11)
QnACPU Programming Manual (Special Function)
Describes the dedicated instructions for special function modules available when using the Q2ACPU(S1), Q3ACPU, and
Q4ACPU. (Sold separately)
SH-4013
(13JF56)
QnACPU Programming Manual (AD57 Instructions)
Describes the dedicated instructions for controlling an AD57(S1) type CRT controller module available when using the
Q2ACPU(S1), Q3ACPU, or Q4ACPU. (Sold separately)
IB-66617
(13JF49)
MELSEC-Q/L/QnA Programming Manual (SFC)
Describes the system configuration, performance specifications, functions, programming, debugging, and error codes for SFC
(MELSAP3) programs. (Sold separately)
SH-080041
(13JF60)
MELSEC-Q/L Programming Manual (MELSAP-L)
Describes programming methods, specifications, and functions for SFC (MELSAP-L) programs. (Sold separately)
SH-080076
(13JF61)
MELSEC-Q Programming/Structured Programming Manual (Process Control Instructions)
Describes the dedicated instructions for process control. (Sold separately)
SH-080316E
(13JF67)
MELSEC-Q/L Programming Manual (Structured Text)
Describes programming using the structured text language. (Sold separately)
SH-080366E
(13JF68)

7
When QCPU is used
When LCPU is used

8
When QnACPU is used

9
GENERIC TERMS
This manual uses the following generic terms unless otherwise described.
Generic term Description
CPU module A generic term for the Basic model QCPU, High Performance model QCPU, Redundant CPU, Universal model QCPU,
LCPU, and QnACPU
QCPU A generic term for the Q00CPU, Q01CPU, Q02CPU, Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU, Q12PRHCPU,
Q25PRHCPU, Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU, Q03UDCPU, Q03UDVCPU, Q03UDECPU,
Q04UDHCPU, Q04UDVCPU, Q04UDPVCPU, Q04UDEHCPU, Q06UDHCPU, Q06UDVCPU, Q06UDPVCPU,
Q06UDEHCPU, Q10UDHCPU, Q10UDEHCPU, Q13UDHCPU, Q13UDVCPU, Q13UDPVCPU, Q13UDEHCPU,
Q20UDHCPU, Q20UDEHCPU, Q26UDHCPU, Q26UDVCPU, Q26UDPVCPU, Q26UDEHCPU, Q50UDEHCPU,
Q100UDEHCPU
QnCPU A generic term for the Q02CPU
QnHCPU A generic term for the Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU
QnPHCPU A generic term for the Q02PHCPU, Q06PHCPU, Q12PHCPU, Q25PHCPU
QnPRHCPU A generic term for the Q12PRHCPU, Q25PRHCPU
LCPU A generic term for the L02SCPU, L02SCPU-P, L02CPU, L02CPU-P, L06CPU, L06CPU-P, L26CPU, L26CPU-P, L26CPU-
BT, L26CPU-PBT
QnACPU A generic term for the Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1, Q2ACPU, Q2ACPU-S1, Q3ACPU,
Q4ACPU, Q4ARCPU
QnA A generic term for the Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1, Q2ACPU, Q2ACPU-S1, Q3ACPU,
Q4ACPU
Q4AR A generic term for the Q4ARCPU
Basic model QCPU A generic term for the Q00JCPU, Q00CPU, Q01CPU
Basic
High Performance model QCPU A generic term for the Q02CPU, Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU
High Performance
Process CPU A generic term for the Q02PHCPU, Q06PHCPU, Q12PHCPU, Q25PHCPU
Redundant CPU A generic term for the Q12PRHCPU, Q25PRHCPU
Universal model QCPU A generic term for the Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU, Q03UDCPU, Q03UDVCPU, Q03UDECPU,
Q04UDHCPU, Q04UDVCPU, Q04UDPVCPU, Q04UDEHCPU. Q06UDHCPU, Q06UDVCPU, Q06UDPVCPU,
Q06UDEHCPU, Q10UDHCPU, Q10UDEHCPU, Q13UDHCPU, Q13UDVCPU, Q13UDPVCPU, Q13UDEHCPU,
Q20UDHCPU, Q20UDEHCPU, Q26UDHCPU, Q26UDVCPU, Q26UDPVCPU, Q26UDEHCPU, Q50UDEHCPU,
Q100UDEHCPU
Universal
Universal model Process CPU A generic term for the Q04UDPVCPU, Q06UDPVCPU, Q13UDPVCPU, Q26UDPVCPU

10 1 GENERAL DESCRIPTION
1GENERAL DESCRIPTION
This manual describes the sequence program instructions used to implement PID control with any of the following CPU
modules.
• Basic model QCPU (first five digits of serial No. are 04122 or later)
• High Performance model QCPU
• Redundant CPU
• Universal model QCPU
•LCPU
•QnACPU
For the Basic model QCPU, High Performance model QCPU, Redundant CPU, Universal model QCPU, and LCPU, the
instructions for PID control by using complete and incomplete derivatives are featured as standard.
The QnACPU has the instructions used to perform PID control by complete derivative (PID control instructions) as standard
features.
Since the incomplete derivative PID control instructions and complete derivative PID control instructions are independent of
each other, they can be executed at the same time.
The following table indicates the CPU modules that can use the incomplete derivative PID control instructions and complete
derivative PID control instructions.
: Usable, : Unusable
*1 Version 7 or earlier version of GX Developer issues an "instruction code alarm" if it loads a new CPU instruction realized with GX
Developer Version 8.
There are the following PID control instructions.
PID control via PID control instructions is implemented by combining the CPU module with the A/D converter module and D/A
converter module.
In the case of the QnACPU, the PID control status can be monitored using the AD57(S1) CRT controller module.
• The Process CPU is not compatible with the PID control instructions described in this manual. To implement
PID control using the Process CPU, use the process control instructions described in the MELSEC-Q
Programming/Structured Programming Manual (Process Control Instructions).
• The Redundant CPU and Universal model Process CPU can use the PID control instructions and process
control instructions.
CPU Module Model Name Incomplete Derivative Complete Derivative
Basic model QCPU First five digits of serial No. are "04121" or earlier 
First five digits of serial No. are "04122" or later 
*1
High Performance model QCPU First five digits of serial No. are "05031" or earlier 
First five digits of serial No. are "05032" or later 
Redundant CPU 
Universal model QCPU 
LCPU 
QnACPU 
Classification Incomplete Derivative Complete Derivative
PID control data setting S(P).PIDINIT PIDINIT(P)
PID operation S(P).PIDCONT PIDCONT(P)
PID control status monitor PID57(P)
Specified loop No. operation stop S(P).PIDSTOP PIDSTOP(P)
Specified loop No. operation start S(P).PIDRUN PIDRUN(P)
Specified loop No. parameter change S(P).PIDPRMW PIDPRMW(P)

1 GENERAL DESCRIPTION
1.1 PID Processing Method 11
1
1.1 PID Processing Method
This section describes the processing method for PID control using PID control instructions. (Page 25 FUNCTIONS OF
PID CONTROL)
Overview of PID Control Processing
Execute PID control with PID control instructions by loading an A/D converter module and a D/A converter module, as shown
below.
In the PID control processing method, as shown above, the PID operation is executed using the set value (SV) and the
process value (PV) read from the A/D converter module, and the manipulated value (MV) is then calculated.
The calculated MV (manipulated value) is output to the D/A converter module.
Operation when PID Operation Instruction Executed
When a PID operation instruction*1 is executed in a sequence program, the sampling cycle is measured and a PID operation
is performed.
PID operation in accordance with the PID operation instruction is executed in preset sampling cycles.
*1 There are the following PID operation instructions.
S.PIDCONT (incomplete derivative)
PIDCONT (complete derivative)

12 2 SYSTEM CONFIGURATION FOR PID CONTROL
2SYSTEM CONFIGURATION FOR PID CONTROL
This chapter describes the system configuration for PID control using the PID control instructions.
Settings of SV, PV, and MV used in the PID control instructions
Set a value within the following range.
• With PID limits (0 to 2000)
• Without PID limits (-32768 to 32767)
*1 When the resolution of the A/D converter module or D/A converter module used for I/O of PID control is other than 0 to 2000, convert the
digital values into 0 to 2000.
CPU Module Type SV, PV, MV
With PID limits*1 Without PID limits
Basic model QCPU 
High Performance model QCPU 
Redundant CPU 
Universal model QCPU 
LCPU 
QnACPU 

2 SYSTEM CONFIGURATION FOR PID CONTROL
2.1 Applicable CPU 13
2
2.1 Applicable CPU
Component Module
Basic model QCPU Q00JCPU, Q00CPU, Q01CPU (First 5 digits of serial No. are 04122 or later)
High Performance model QCPU Q02CPU, Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU
Redundant CPU Q12PRHCPU, Q25PRHCPU
Universal model QCPU Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU, Q03UDCPU, Q03UDVCPU, Q03UDECPU, Q04UDHCPU,
Q04UDVCPU, Q04UDPVCPU, Q04UDEHCPU, Q06UDHCPU, Q06UDVCPU, Q06UDPVCPU, Q06UDEHCPU,
Q10UDHCPU, Q10UDEHCPU, Q13UDHCPU, Q13UDVCPU, Q13UDPVCPU, Q13UDEHCPU, Q20UDHCPU,
Q20UDEHCPU, Q26UDHCPU, Q26UDVCPU, Q26UDPVCPU, Q26UDEHCPU, Q50UDEHCPU, Q100UDEHCPU
LCPU L02SCPU, L02SCPU-P, L02CPU, L02CPU-P, L06CPU, L06CPU-P, L26CPU, L26CPU-P, L26CPU-BT, L26CPU-PBT
QnACPU Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1, Q2ACPU, Q3ACPU, Q4ACPU, Q4ARCPU

14 3 PID CONTROL SPECIFICATIONS
3.1 PID Control by incomplete derivative
3PID CONTROL SPECIFICATIONS
This section gives the specifications PID operation using PID control instructions.
3.1 PID Control by incomplete derivative
Performance specifications
The performance specifications for PID control are tabled below.
: Unusable
Item Specifications
With PID limits Without PID limits QnACPU
Basic model
QCPU
High Performance
model QCPU,
Redundant CPU,
Universal model
QCPU, LCPU
Basic model
QCPU
High Performance
model QCPU,
Redundant CPU,
Universal model
QCPU, LCPU
Number of PID control loops 8 loops (maximum) 32 loops (maximum) 8 loops (maximum) 32 loops (maximum) 
Sampling cycle TS0.01 to 60.00s 
PID operation method Process value differentiation incomplete derivative (forward operation/reverse operation) 
PID
constant
setting
range
Proportional
constant
KP0.01 to 100.00 
Integral
constant
TI0.1 to 3000.0s 
Derivative
constant
TD0.00 to 300.00s 
Derivative gain KD0.00 to 300.00 
SV (set value) setting range SV 0 to 2000 -32768 to 32767 
PV (process value) setting
range
PV -50 to 2050 -32768 to 32767 
MV (manipulated value) output
range
MV

3 PID CONTROL SPECIFICATIONS
3.1 PID Control by incomplete derivative 15
3
PID operation block diagram and operation expressions
PID operation block diagram
The PID operation block diagram for incomplete derivative is shown below.
Operation expressions
The operation expressions for PID control using PID control instructions are indicated below.
*1 PVfn is calculated using the following expression.
Therefore, it is the same as the PV (process value) of the input data as long as the filter coefficient is not set for the input data.
Process Value after Filtering PVfn = PVn+ (PVfn-1 - PVn)
PVn: Process value of the present sampling cycle
: Filter coefficient
PVfn-1: Process value of the preceding sampling cycle (after filtering)
PVfn is stored in the I/O data area. (Page 51 I/O Data)
Name Operation Expressions Meanings of Symbols
Process value
differentiation
Incomplete
derivative
Forward
operation
EVn: Deviation in the present sampling cycle
EVn-1: Deviation in the preceding sampling cycle
SV: Set value
PVfn: Process value of the present sampling cycle (after
filtering)
PVfn-1: Process value of the preceding sampling cycle
(after filtering)
PVfn-2: Process value of the sampling cycle two cycles
before (after filtering)
MV: Output change value
MVn: Present manipulation value
Dn: Present derivative term
Dn-1: Derivative term of the preceding sampling cycle
KP: Proportional constant
TS: Sampling cycle
TI: Integral constant
TD: Derivative constant
KD: Derivative gain
Reverse
operation

16 3 PID CONTROL SPECIFICATIONS
3.1 PID Control by incomplete derivative
PID control instruction list
A list of the instructions used to execute PID control is given below.
: Usable, : Unusable
*1 For the Basic model QCPU, High Performance model QCPU, Redundant CPU, Universal model QCPU, and LCPU, "with or without PID
limits" can be selected.
Refer to Sections 5.1 and 5.2 for details of the setting range when "with/without PID limits" has been selected.
Page 36 PID Control Data, Page 51 I/O Data
Instruction Name Processing Details CPU
QCPU, LCPU QnACPU
S.PIDINIT Sets the reference data for PID operation. *1 
S.PIDCONT Executes PID operation with the SV (set value) and the PV (process value). *1 
S.PIDSTOP
S.PIDRUN
Stops or starts PID operation for the set loop No. 
S.PIDPRMW Changes the operation parameters for the designated loop number to PID
control data.
*1 

3 PID CONTROL SPECIFICATIONS
3.1 PID Control by incomplete derivative 17
3
PID control instruction list
The PID control instruction list has the format indicated below:
■How to Read the PID control Instruction List
Classification of instructions according to their application.
Instruction names written in a sequence program.
Symbols used in the ladder diagram.
Processing for each instruction.
Details of execution condition for each instruction are given below.
Number of instruction steps
For details on the number of steps, refer to the Programming Manual (Common Instructions) for the CPU module used.
A circle indicates that subset processing is possible.
- indicates that subset processing is impossible.
For details on subset processing, refer to the Programming Manual (Common Instructions) for the CPU module used.
Indicates the page number in this manual where a detailed description for the instruction can be found.
Symbol Execution Condition
Indicates an instruction that is executed for the duration that the condition for its execution is ON.
When the condition before the instruction is OFF, the instruction is not executed and no processing is carried out.
Indicates an instruction that is executed once only at the leading edge (OFF to ON) of the condition for its execution; thereafter the
instruction will not be executed, and no processing will be carried out, even if the condition is ON.
ÒÓ Ô Õ Ö×ØÙ

18 3 PID CONTROL SPECIFICATIONS
3.1 PID Control by incomplete derivative
■PID Control Instruction List
Category Instruction
Symbol
Ladder Format Processing Details Execution
Condition
Number
of Basic
Steps
Subset
Process
ing
Page
PID
Control
data
setting
S.PIDINIT Sets the PID control data stored in the
word device (designated by ).
7 - Page 60
PID control
data
settings
PID
operation
S.PIDCONT Executes PID operation with the SV (set
value) and the PV (process value)
designated by and stores the PID
operation results in the MV (manipulated
value) area of the word device designated
by .
7 - Page 61
PID
operation
Operation
stop
S.PIDSTOP Stops the PID operation at the loop
number designated by .
7 - Page 63
Operation
stop/start
of
designated
loop no.
Operation
start
S.PIDRUN Starts the operation at the loop number
designated by .
6 - Page 63
Operation
stop/start
of
designated
loop no.
Parameter
change
S.PIDPRMW Changes the operation parameter for the
loop number designated by to the PID
control data stored in the word device
designated by
8 - Page 64
Parameter
change at
designated
loop
S
S
S
n
n
n
S