Mitsubishi QCPU Owner's manual

A - 1
•SAFETY PRECAUTIONS •
(You must read these cautions before using the product)
As for the use of the product, please carefully read this manual and the related manuals introduced later.
Also, please pay attention to safety adequately and manage the product correctly.
The safety cautions shown in this manual apply to the product only.
In this manual, the safety precautions are ranked as "DANGER" and "CAUTION".
!DANGER
CAUTION
!
Indicates that incorrect handling may cause hazardous conditions,
resulting in death or severe injury.
Indicates that incorrect handling may cause hazardous conditions,
resulting in medium or slight personal injury or physical damage.
Note that the !CAUTION level may lead to a serious consequence according to the circumstances.
Always follow the instructions of both levels because they are important to personal safety.
Please store this manual in order to read whenever it is necessary. Also, always forward this manual to
the end users.
[Design Precautions]
!DANGER
•Install a safety circuit external to the programmable controller that keeps the entire system safe
even when there are problems with the external power supply or the programmable controller.
Otherwise, it may cause an output error or an operating error, resulting in an accident.
(1) Configure a circuit such as an emergency stop circuit and a protective circuit on the outside
of the programmable logic controller.
(2) When the programmable controller detects the following problems, it will stop calculation
and turn off all outputs.
• An overcurrent protective device or an overvoltage protective device in a power supply
module start running.
• A watchdog timer error or others is detected with self-checking function in the
programmable controller CPU.
All outputs may be turned on, when an error occurs in the part of I/O controlling or others
that the programmable controller CPU cannot detect. Build a fail safe circuit exterior to the
programmable controller to keep the entire system safe.
As for the fail safe circuit, refer to a CPU module User’s Manual.
• Configure a circuit that turns on an external power supply when the main power of
programmable controller is turned on. If the external power supply is turned on first, it could
result in an output error or an operating error.

A - 2
[Design Precautions]
!DANGER
• When connecting a peripheral device to the CPU module or connecting a personal computer or
others to an intelligent function module, always configure an interlock circuit in the sequence
program to ensure that the whole system always operate safely.
Also, make sure to read this manual carefully and check all operations for safety first before
executing other control (program changes, changes of operation status (and status control)) of
the operating sequence.
Especially for the control described above on the remote sequence from an external device, an
immediate action may not be taken for a programmable controller’s trouble due to a data
communication fault.
Configure the interlock circuit in the sequence program. Simultaneously a recovery method for
system, in which a data communications fault occurs, should be determined between the
external device and the programmable controller CPU.
[Startup/Maintenance Precaution]
!CAUTION
• Make sure to read this manual carefully and check all operations for safety first before
connecting a peripheral device to an operating CPU module online (particularly program
changes, forced outputs, and changes of operation status). Otherwise, an operating error may
cause damage or problems with the modules.

A - 3
REVISIONS
* The manual number is given on the bottom left of the back cover.
Print Date * Manual Number Revision
Dec., 1999 SH (NA) 080040-A First edition
Jun., 2001 SH (NA) 080040-B Partial addition
About Manuals, Chapter 1, Chapter 2, Section 2.1, 3.1, 3.2, 3.3, 3.3.1,
4.2.3, 4.3.2, 4.3.5, Chapter 5, Section 5.1, 5.2, Chapter 6, Chapter 7,
Section 8.1, 8.2
Apr., 2002 SH (NA) 080040-C Correction
Chapter 1, Chapter 7, Section 8.1, 8.2, 8.3, 8.4, 8.5
Jan., 2003 SH (NA) 080040-D • Addition of use of Basic model QCPU
• Addition of explanation of incomplete derivative
Overall reexamination
Mar., 2003 SH (NA) 080040-E • Addition of explanation of incomplete derivative to High Performance
model QCPU
Dec., 2003 SH (NA) 080040-F Correction
Chapter 1
Jun., 2004 SH (NA) 080040-G Addition of Redundant CPU
Partial addition
About Manuals, Chapter 1, Chapter 2, Section 2.1, 3.1.1, 3.1.3, 3.2.1,
3.2.3, 4.3.5, 5.1, 5.2, Chapter 6, Chapter 7, Section 8.1.1 to 8.1.4,
Section 9.1.1 to 9.1.5, 9.2, Appendix 1
Sep., 2006 SH (NA) 080040-H Partial addition
Section 4.2.5, Appendix 2
Apr.,2007 SH (NA) 080040-I Addition of Universal model QCPU
Addition module
Q02UCPU, Q03UDCPU, Q04UDHCPU, Q06UDHCPU
Partial correction
GENERIC TERMS AND ABBREVIATIONS USED IN THIS MANUAL,
Chapter 1, Chapter 2, Section 2.1, 3.1.1, 3.1.3, 3.2.1, 3.2.3, 5.1, Chapter 6,
Chapter 7, 8.1.1 to 8.1.5, 9.1.1 to 9.1.5, Appendix 1
Mar.,2008 SH (NA) 080040-J Addition of Universal model QCPU
Addition module
Q13UDHCPU, Q26UDHCPU
Partial correction
GENERIC TERMS AND ABBREVIATIONS USED IN THIS MANUAL,
Section 2.1, Appendix 1

A - 4
* The manual number is given on the bottom left of the back cover.
Print Date * Manual Number Revision
May,2008 SH (NA) 080040-K Revision due to the addition of Process CPU and Universal model QCPU
Addition module
Q03UDECPU, Q04UDEHCPU, Q06UDEHCPU, Q13UDEHCPU,
Q26UDEHCPU
Q02PHCPU, Q06PHCPU
Partial correction
GENERIC TERMS AND ABBREVIATIONS USED IN THIS MANUAL,
Section 2.1, Appendix 1
Japanese Manual Version SH-080022-K
This manual confers no industrial property rights or any rights of any other kind, nor does it confer any patent licenses.
Mitsubishi Electric Corporation cannot be held responsible for any problems involving industrial property rights which
may occur as a result of using the contents noted in this manual.
©1999 MITSUBISHI ELECTRIC CORPORATION

A - 5
INTRODUCTION
Thank you for choosing the Mitsubishi MELSEC-Q/QnA Series of Programmable Logic Controllers.
Please read this manual carefully so that the equipment is used to its optimum. A copy of this manual should
be forwarded to the end User.
CONTENTS
SAFETY CAUTIONS ......................................................................................................................................A- 1
REVISIONS .....................................................................................................................................................A- 3
CONTENTS.....................................................................................................................................................A- 5
About Manuals ................................................................................................................................................A- 8
Generic Terms and Abbreviations Used in This Manual ..............................................................................A-11
1. GENERAL DESCRIPTION 1 – 1 to 1 - 3
1.1 PID Processing Method ........................................................................................................................... 1 - 3
2. SYSTEM CONFIGURATION FOR PID CONTROL 2 - 1 to 2 - 2
2.1 Applicable PLC CPU................................................................................................................................ 2 - 2
3. PID CONTROL SPECIFICATIONS 3 - 1 to 3 - 14
3.1 PID Control by Incomplete derivative ...................................................................................................... 3 - 1
3.1.1 Performance specifications............................................................................................................... 3 - 1
3.1.2 PID operation block diagram and operation expressions ................................................................ 3 - 2
3.1.3 PID control instruction list.................................................................................................................. 3 - 3
3.2 PID Control by Complete Derivative........................................................................................................ 3 - 8
3.2.1 Performance specifications............................................................................................................... 3 - 8
3.2.2 PID operation block diagram and operation expressions ................................................................ 3 - 9
3.2.3 PID control instruction list................................................................................................................ 3 - 10
4. FUNCTIONS OF PID CONTROL 4 - 1 to 4 - 14
4.1 Outline of PID Control .............................................................................................................................. 4 - 1
4.2 Functions of PID Control.......................................................................................................................... 4 - 2
4.2.1 Operation method.............................................................................................................................. 4 - 2
4.2.2 Forward operation and reverse operation ........................................................................................ 4 - 2
4.2.3 Proportionate operation (P operation) .............................................................................................. 4 - 4
4.2.4 Integrating operation (I operation) .................................................................................................... 4 - 5
4.2.5 Differentiating operation (D operation) ............................................................................................. 4 - 6
4.2.6 PID operation..................................................................................................................................... 4 - 8
4.3 Other Functions........................................................................................................................................ 4 - 9
4.3.1 Bumpless changeover function ........................................................................................................ 4 - 9
4.3.2 MV higher/lower limit control function............................................................................................. 4 - 10
4.3.3 Monitorning PID control with the AD57(S1) (QnACPU only)......................................................... 4 - 11
4.3.4 Function for transfer to the SV storage device for the PV in manual mode.................................. 4 - 12
4.3.5 Changing the PID control data or input/output data setting range (QCPU only) ......................... 4 – 13

A - 6
5. PID CONTROL PROCEDURE 5 - 1 to 5 - 24
5.1 PID Control Data ...................................................................................................................................... 5 - 4
5.1.1 Number of loops to be used and the number of loops to be executed in a single scan............... 5 - 15
5.1.2 Sampling cycle ................................................................................................................................ 5 - 16
5.2 I/O Data .................................................................................................................................................. 5 - 18
6. PID CONTROL INSTRUCTIONS 6 - 1 to 6 - 2
7. HOW TO READ EXPLANATIONS FOR INSTRUCTIONS 7 - 1 to 7 - 2
8. INCOMPLETE DERIVATIVE PID CONTROL INSTRUCTIONS AND PROGRAM EXAMPLES
8 - 1 to 8 - 16
8.1 PID Control Instructions ........................................................................................................................... 8 - 1
8.1.1 PID control data settings S.PIDINIT,SP.PIDINIT .......................................... 8 - 2
8.1.2 PID operation S.PIDCONT,SP.PIDCONT................................... 8 - 3
8.1.3 Operation stop/start of designated loop no. S.PIDSTOP,SP.PIDSTOP,S.PIDRUN,SP.PIDRUN
.................................................................................................................................................................... 8 - 5
8.1.4 Parameter change at designated loop S.PIDPRMW,SP.PIDPRMW ................................ 8 - 6
8.2 PID Control Program Examples .............................................................................................................. 8 - 8
8.2.1 System configuration for program examples.................................................................................... 8 - 8
8.2.2 Program example for automatic mode PID control.......................................................................... 8 - 9
8.2.3 Program example for changing the PID control mode between automatic and manual .............. 8 - 13
9. COMPLETE DERIVATIVE PID CONTROL INSTRUCTIONS AND PROGRAM EXAMPLES 9 - 1 to 9 - 28
9.1 PID Control Instructions ...........................................................................................................................9 - 1
9.1.1 PID control data settings PIDINIT,PIDINITP................................................. 9 - 2
9.1.2 PID control PIDCONT,PIDCONTP.......................................... 9 - 3
9.1.3 Monitoring PID control status (QnACPU only) PID57,PID57P....................................................... 9 - 5
9.1.4 Operation stop/start of designated loop no. PIDSTOP,PIDSTOPP,PIDRUN,PIDRUNP ......... 9 - 8
9.1.5 Parameter change at designated loop PIDPRMW,PIDPRMWP ....................................... 9 - 9
9.2 PID Control Program Examples (QCPU only) ...................................................................................... 9 - 11
9.2.1 System configuration for program examples.................................................................................. 9 - 11
9.2.2 Program example for automatic mode PID control........................................................................ 9 - 12
9.2.3 Program example for changing the PID control mode between automatic and manual .............. 9 - 15
9.3 PID Control Program Examples (QnACPU only).................................................................................. 9 - 19
9.3.1 System configuration for program examples.................................................................................. 9 - 19
9.3.2 Program example for automatic mode PID control........................................................................ 9 - 20
9.3.3 Program example for changing the PID control mode between automatic and manual ............. 9 – 24

A - 7
APPENDIX APP - 1 to APP - 3
Appendix 1 Processing Time List .............................................................................................................APP - 1
Appendix 2 Anti-Reset Windup Measure .................................................................................................APP - 3

A - 8
About Manuals
The following manuals are also related to this product.
In necessary, order them by quoting the details in the tables below.
Related Manuals
Manual Name Manual Number
(Model Code)
QCPU User's Manual (Function Explanation, Program Fundamentals)
Describes the functions, programming procedures, devices, etc. necessary to create programs.
(Sold separately)
SH-080484ENG
(13JR73)
QnACPU Programming Manual (Fundamentals)
Describes how to create programs, the names of devices, parameters, and types of program.
(Sold separately)
IB-66614
(13JF46)
QCPU (Q mode) /QnACPU Programming Manual (Common Instructions)
Describes how to use sequence instructions, basic instructions, and application instructions.
(Sold separately)
SH-080039
(13JF58)
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)

A - 9
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.
(1) When QCPU is used
QCPU
User's Manual
(Function Explanation,
Program Fundamentals)
Describes the functions,
executable programs,
I/O processing and device
names of the QCPU.
QCPU (Q mode)/
QnACPU
Programming
Manual
(Common
Instructions)
QCPU (Q mode)/
QnACPU
Programming
Manual
(PID Control
Instructions)
QCPU (Q mode)/
QnACPU
Programming
Manual
(SFC)
Describes the
instructions other
than those given
on the ri
g
ht.
Describes the
instructions used for
PID control.
Describes SFC.
This manual
QCPU (Q mode)
Programming
Manual
(MELSAP-L)
Describes MELSAP-L.
QCPU (Q mode)
Programming
Manual
(Structured Text)
Describes the
structured text.

A - 10
(2) When QnACPU is used
QnACPU
Programming
Manual
(Fundamentals)
QCPU (Q mode)/
QnACPU
Programming
Manual
(Common
Instructions)
QnACPU
Programming
Manual
(Special Function
Modules)
QnACPU
Programming
Manual
(AD57 Commands)
QCPU (Q mode)/
QnACPU
Programming
Manual
(PID Control
Instructions)
QCPU (Q mode)/
QnACPU
Programming
Manual
(SFC)
Describes the programs, I/O processing,
device names, etc. that can be executed
by the QnACPU.
Describes the
instructions other
than those given
on the right.
Describes the
instructions for the
special function
modules such as the
AJ71QC24 and
AJ71PT32-S3.
Describes the AD57
commands for
controlling the
AD57/AD58.
Describes the
instructions used
for PID control.
Describes SFC.
This manual
Q4ARCPU
Programming
Manual
(Application PID
Instructions)
Describes the
instructions used
for applied PID control.
Q4ARCPU only

A - 11
Generic Terms and Abbreviations Used in This Manual
This manual uses the following generic terms and abbreviations unless otherwise described.
Generic term/abbreviation Description of generic term/abbreviation
CPU module Generic term of Basic model QCPU, High Performance model QCPU,
Redundant CPU, Universal model QCPU, QnACPU
QnACPU Abbreviation of Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1,
Q2ACPU, Q2ACPU-S1, Q3ACPU, Q4ACPU, Q4ARCPU
QnA Abbreviation of Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1,
Q2ACPU, Q2ACPU-S1, Q3ACPU, Q4ACPU
Q4AR Abbreviation of Q4ARCPU
QCPU
Abbreviation of Q00CPU, Q01CPU, Q02CPU, Q02HCPU, Q06HCPU,
Q12HCPU, Q25HCPU, Q12PRHCPU, Q25PRHCPU, Q02UCPU,
Q03UDCPU, Q04UDHCPU, Q06UDHCPU, Q13UDHCPU, Q26UDHCPU,
Q03UDECPU, Q04UDEHCPU, Q06UDEHCPU, Q13UDEHCPU,
Q26UDEHCPU
QnCPU Abbreviation of Q02CPU
QnHCPU Abbreviation of Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU
QnPHCPU Abbreviation of Q02PHCPU, Q06PHCPU, Q12PHCPU, Q25PHCPU
QnPRHCPU Abbreviation of Q12PRHCPU, Q25PRHCPU
QnUD(H)CPU
Abbreviation of Q03UDCPU, Q04UDHCPU, Q06UDHCPU,
Q13UDHCPU, Q26UDHCPU, Q03UDECPU, Q04UDEHCPU,
Q06UDEHCPU, Q13UDEHCPU, Q26UDEHCPU
Basic model QCPU
Basic Generic term of Q00JCPU, Q00CPU, Q01CPU
High Performance model QCPU
High Performance Generic term of Q02CPU, Q02HCPU, Q06HCPU, Q12HCPU, Q25HCPU
Process CPU Generic term of Q02PHCPU, Q06PHCPU, Q12PHCPU, Q25PHCPU
Redundant CPU Generic term of Q12PRHCPU, Q25PRHCPU
Universal model QCPU
Universal
Generic term of Q02UCPU, Q03UDCPU, Q04UDHCPU, Q06UDHCPU,
Q13UDHCPU, Q26UDHCPU, Q03UDECPU, Q04UDEHCPU,
Q06UDEHCPU, Q13UDEHCPU, Q26UDEHCPU

A - 12
MEMO

1 - 1
MELSEC-Q/Qn
A
1. GENERAL DESCRIPTION
1
1. GENERAL 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
• QnACPU
The Basic model QCPU, High Performance model QCPU, Redundant CPU, and
Universal model QCPU have the instructions used to perform PID control by
incomplete derivative (PID control instructions) and the instructions used to perform
PID control by complete derivative (PID control instructions) as standard features.
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.
CPU Module Model Name Incomplete
Derivative
Complete
Derivative
First five digits of serial No. are
"04121" or earlier
Basic model QCPU First five digits of serial No. are
"04122" or later
First five digits of serial No. are
"05031" or earlier
High Performance model
QCPU First five digits of serial No. are
"05032" or later *1
Redundant CPU
Universal model QCPU
QnACPU
: 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.

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MELSEC-Q/Qn
A
1. GENERAL DESCRIPTION
There are the following PID control instructions.
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)
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.
POINT
(1) 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 QnPHCPU/QnPRHCPU Programming Manual
(Process Control Instructions).
(2) The Redundant CPU can use the PID control instructions and process control
instructions.

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MELSEC-Q/Qn
A
1. GENERAL DESCRIPTION
1.1 PID Processing Method
This section describes the processing method for PID control using PID control
instructions. (For details on PID operations, see Chapter 4.)
Execute PID control with PID control instructions by loading an A/D converter module
and a D/A converter module, as shown in Figure 1.1.
CPU module
Set value
PID control instructions
PID operation
PV
SV D/A conversion
module
A/D conversion
module Sensor
Manual MV
Manual/automatic
changeover
Automatic
MV
MV
PV
SV: Set Value
PV: Process Value
MV: Manipulated Value
Controlled
system
Figure 1.1 Overview of PID Control Processing
In the PID control processing method, as shown in Figure 1.1, 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.
When a PID operation instruction* 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.
Sequence program
Step 0
PID operation
instruction
execution
Sampling cycle
Step 0 Step 0 Step 0 Step 0
Measurement of
sampling cycle
END END END END
Measurement of
sampling cycle
Measurement of
sampling cycle
Sampling cycle
Measurement of
sampling cycle
PID operation
Measurement of
sampling cycle
PID operation
PID operation
instruction
execution
PID operation
instruction
execution
PID operation
instruction
execution
PID operation
instruction
execution
Figure 1. 2 Operation when PID Operation Instruction Executed
REMARK
*: There are the following PID operation instructions.
S.PIDCONT (incomplete derivative)
PIDCONT (complete derivative)

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MELSEC-Q/Qn
A
1. GENERAL DESCRIPTION
MEMO

2 - 1
MELSEC-Q/Qn
A
2. SYSTEM CONFIGURATION FOR PID CONTROL
2
2. SYSTEM CONFIGURATION FOR PID CONTROL
This chapter describes the system configuration for PID control using the PID control
instructions.
For the modules that can be used to configure a system, refer to the following manual.
• Basic model QCPU, High Performance model QCPU, Universal model QCPU: MELSEC-Q DATA
BOOK
• QnACPU: User's manual (details) of the used CPU module
CRT
Operation panel
D/A conversion
module
A/D conversion
module
Main base unit
Extension
cable
Extension base
unit
For PV (process value) input
For MV (manipulated
value) output
For PID control monitoring (Only QnACPU)
CRT control
module
AD57 or AD57-S1
only
CPU module

2 - 2
MELSEC-Q/Qn
A
2. SYSTEM CONFIGURATION FOR PID CONTROL
POINT
SV, PV and MV used with the PID control instructions may be set either with the
fixed values of 0 to 2000 or to any values according to the used module.
Refer to Section 4.3.5 for details.
SV, PV, MV
CPU Module Type 0 to 2000 fixed * Any setting
Basic model QCPU
High Performance model QCPU
Redundant CPU
Universal model QCPU
QnACPU ×
: Can be set, : Cannot be set
*: 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.
2.1 Applicable PLC 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
Q02UCPU, Q03UDCPU, Q04UDHCPU, Q06UDHCPU,
Q13UDHCPU, Q26UDHCPU, Q03UDECPU, Q04UDEHCPU,
Q06UDEHCPU, Q13UDEHCPU, Q26UDEHCPU
QnACPU Q2ASCPU, Q2ASCPU-S1, Q2ASHCPU, Q2ASHCPU-S1
Q2ACPU, Q3ACPU, Q4ACPU, Q4ARCPU