Mitsubishi Electric MELSEC-L02SCPU User manual

MELSEC-L CPU Module User's Manual
(Built-In I/O Function)
-L02SCPU
-L02SCPU-P
-L02CPU
-L02CPU-P
-L06CPU
-L06CPU-P
-L26CPU
-L26CPU-P
-L26CPU-BT
-L26CPU-PBT

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.
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.
WARNING
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 minor or moderate injury or property damage.

2
[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) Machine OPR (Original Point Return) of the positioning function is controlled by two kinds of data:
an OPR direction and an OPR speed. Deceleration starts when the near-point dog signal turns on.
If an incorrect OPR direction is set, motion control may continue without deceleration. To prevent
machine damage caused by this, configure an interlock circuit external to the programmable
controller.
(3) When the CPU module detects an error during control by the positioning function, the motion
slows down and stops.
(4) 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.
(5) 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).
(6) Outputs may remain on or off due to a failure of a component such as a transistor in an output
circuit. Configure an external circuit for monitoring output signals that could cause a serious
accident.
●In an output circuit, when a load current exceeding the rated current or an overcurrent caused by a
load short-circuit flows for a long time, it may cause smoke and fire. To prevent this, configure an
external safety circuit, such as a fuse.
●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.
●For the operating status of each station after a communication failure, refer to relevant manuals for
each network. Incorrect output or malfunction due to a communication failure may result in an
accident.

3
[Design Precautions]
[Design Precautions]
WARNING
●When changing data from a peripheral device connected to the CPU module during operation,
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.
●An absolute position restoration by the positioning function may turn off the servo-on signal (servo off)
for approximately 20ms, and the motor may run unexpectedly. If this causes a problem, provide an
electromagnetic brake to lock the motor during absolute position restoration.
CAUTION
●Do not install the control lines or communication cables together with the main circuit lines or power
cables. Keep a distance of 100mm or more between them. Failure to do so may result in malfunction
due to noise.
●During control of an inductive load such as a lamp, heater, or solenoid valve, a large current
(approximately ten times greater than normal) may flow when the output is turned from off to on.
Therefore, use a module that has a sufficient current rating.
●After the CPU module is powered on or is reset, the time taken to enter the RUN status varies
depending on the system configuration, parameter settings, and/or program size. Design circuits so
that the entire system will always operate safely, regardless of the time.

4
[Installation Precautions]
[Installation Precautions]
[Wiring Precautions]
WARNING
●Shut off the external power supply (all phases) used in the system before mounting or removing a
module. Failure to do so may result in electric shock or cause the module to fail or malfunction.
CAUTION
●Use the programmable controller in an environment that meets the general specifications in the
MELSEC-L CPU Module User's Manual (Hardware Design, Maintenance and Inspection). Failure to
do so may result in electric shock, fire, malfunction, or damage to or deterioration of the product.
●To interconnect modules, engage the respective connectors and securely lock the module joint levers
until they click. Incorrect interconnection may cause malfunction, failure, or drop of the module.
●Do not directly touch any conductive parts and electronic components of the module. Doing so can
cause malfunction or failure of the module.
●Securely connect an extension cable to the connectors of a branch module and an extension module.
After connections, check that the cable is inserted completely. Poor contact may cause malfunction.
●When using an SD memory card, fully insert it into the SD memory card slot. Check that it is inserted
completely. Poor contact may cause malfunction.
●Do not directly touch any conductive parts and electronic components of the module or SD memory
card. Doing so can cause malfunction or failure of the module.
WARNING
●Shut off the external power supply (all phases) used in the system before wiring. Failure to do so may
result in electric shock or cause the module to fail or malfunction.
●After installation and wiring, attach the included terminal cover to the module before turning it on for
operation. Failure to do so may result in electric shock.

5
[Wiring Precautions]
CAUTION
●Individually ground the FG terminal of the programmable controller with a ground resistance of 100
or less. Failure to do so may result in electric shock or malfunction.
●Use applicable solderless terminals and tighten them within the specified torque range. If any spade
solderless terminal is used, it may be disconnected when a terminal block screw comes loose,
resulting in failure.
●Check the rated voltage and terminal layout before wiring to the module, and connect the cables
correctly. Connecting a power supply with a different voltage rating or incorrect wiring may cause a fire
or failure.
●Connectors for external devices must be crimped or pressed with the tool specified by the
manufacturer, or must be correctly soldered. Incomplete connections may cause short circuit, fire, or
malfunction.
●Securely connect the connector to the module.
●Do not install the control lines or communication cables together with the main circuit lines or power
cables. Failure to do so may result in malfunction due to noise.
●Place the cables in a duct or clamp them. If not, dangling cable may swing or inadvertently be pulled,
resulting in damage to the module or cables or malfunction due to poor contact.
●Check the interface type and correctly connect the cable. Incorrect wiring (connecting the cable to an
incorrect interface) may cause failure of the module and external device.
●Tighten the terminal block screws within the specified torque range. Undertightening can cause short
circuit, fire, or malfunction. Overtightening can damage the screw and/or module, resulting in drop,
short circuit, or malfunction.
●When disconnecting the cable from the module, do not pull the cable by the cable part. For the cable
with connector, hold the connector part of the cable. For the cable connected to the terminal block,
loosen the terminal screw. Pulling the cable connected to the module may result in malfunction or
damage to the module or cable.
●Prevent foreign matter such as dust or wire chips from entering the module. Such foreign matter can
cause a fire, failure, or malfunction.
●A protective film is attached to the top of the module to prevent foreign matter, such as wire chips,
from entering the module during wiring. Do not remove the film during wiring. Remove it for heat
dissipation before system operation.
●To use the high-speed counter function, ground the shield cable on the encoder side (relay box).
Always ground the FG and LG terminals to the protective ground conductor. Failure to do so may
cause malfunction.
●Mitsubishi programmable controllers must be installed in control panels. Connect the main power
supply to the power supply module in the control panel through a relay terminal block.
Wiring and replacement of a power supply module must be performed by qualified maintenance
personnel with knowledge of protection against electric shock.
For wiring methods, refer to the MELSEC-L CPU Module User's Manual (Hardware Design,
Maintenance and Inspection).

6
[Startup and Maintenance Precautions]
[Startup and Maintenance Precautions]
WARNING
●Do not touch any terminal while power is on. Doing so will cause electric shock or malfunction.
●Correctly connect the battery connector. Do not charge, disassemble, heat, short-circuit, solder, or
throw the battery into the fire. Also, do not expose it to liquid or strong shock.
Doing so will cause the battery to produce heat, explode, ignite, or leak, resulting in injury and fire.
●Shut off the external power supply (all phases) used in the system before cleaning the module or
retightening the terminal block screws. Failure to do so may result in electric shock.
CAUTION
●Before performing online operations (especially, program modification, forced output, and operating
status change) for the running CPU module from the peripheral device connected, read relevant
manuals carefully and ensure the safety. Improper operation may damage machines or cause
accidents.
●Do not disassemble or modify the module. Doing so may cause failure, malfunction, injury, or a fire.
●Use any radio communication device such as a cellular phone or PHS (Personal Handy-phone
System) more than 25cm away in all directions from the programmable controller. Failure to do so
may cause malfunction.
●Shut off the external power supply (all phases) used in the system before mounting or removing a
module. Failure to do so may cause the module to fail or malfunction.
●Tighten the terminal block screws within the specified torque range. Undertightening can cause drop
of the component or wire, short circuit, or malfunction. Overtightening can damage the screw and/or
module, resulting in drop, short circuit, or malfunction.
●After the first use of the product (module, display unit, and terminal block), the number of
connections/disconnections is limited to 50 times (in accordance with IEC 61131-2). Exceeding the
limit may cause malfunction.
●After the first use of the SD memory card, do not insert/remove the memory card more than 500 times.
Exceeding the limit may cause malfunction.
●Do not drop or apply shock to the battery to be installed in the module. Doing so may damage the
battery, causing the battery fluid to leak inside the battery. If the battery is dropped or any shock is
applied to it, dispose of it without using.
●Before handling the module, touch a conducting object such as a grounded metal to discharge the
static electricity from the human body. Failure to do so may cause the module to fail or malfunction.
●Before testing the operation by the positioning function, set a low speed value for the speed limit
parameter so that the operation can be stopped immediately upon occurrence of a hazardous
condition.

7
[Disposal Precautions]
[Transportation Precautions]
CAUTION
●When disposing of this product, treat it as industrial waste. When disposing of batteries, separate
them from other wastes according to the local regulations. (For details on battery regulations in EU
member states, refer to the MELSEC-L CPU Module User's Manual (Hardware Design, Maintenance
and Inspection).)
CAUTION
●When transporting lithium batteries, follow the transportation regulations. (For details on the regulated
models, refer to the MELSEC-L CPU Module User's Manual (Hardware Design, Maintenance and
Inspection).)

8
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.

9
INTRODUCTION
Thank you for purchasing the Mitsubishi MELSEC-L series programmable controllers.
This manual describes the functions of the external I/O interface of the LCPU and programming.
Before using this product, please read this manual and the relevant manuals carefully and develop familiarity with the
functions and performance of the MELSEC-L series programmable controller to handle the product correctly.
When applying the program examples introduced in this manual to an actual system, ensure the applicability and
confirm that it will not cause system control problems.
Please make sure that the end users read this manual.
Relevant CPU modules
Remark
●This manual describes only built-in I/O functions for the CPU module. For the functions except for built-in I/O functions of
the CPU module, refer to the following.
MELSEC-L CPU Module User's Manual (Function Explanation, Program Fundamentals)
MELSEC-L CPU Module User's Manual (Built-In Ethernet Function)
QnUDVCPU/LCPU User's Manual (Data Logging Function)
●Unless otherwise specified, this manual describes examples of assigning from X0 to XF for input numbers and from Y0 to
Y7 for output numbers in each function. For I/O number assignment, refer to the following.
MELSEC-L CPU Module User's Manual (Function Explanation, Program Fundamentals)
●Unless otherwise specified, Chapter 7 POSITIONING FUNCTION in this manual is described as using examples of the
setting, special relay, special register, dedicated instruction, error code and warning code supported for Axis 1.
●Unless otherwise specified, Chapter 8 HIGH-SPEED COUNTER FUNCTION in this manual is described as using
examples of the setting, special relay, special register, dedicated instruction, error code and warning code supported for
CH1.
CPU module Model
LCPU L02SCPU, L02SCPU-P, L02CPU, L02CPU-P, L06CPU, L06CPU-P, L26CPU, L26CPU-P,
L26CPU-BT, L26CPU-PBT

10
RELEVANT MANUALS
(1) CPU module user's manual
(2) Programming manual
(3) Operating manual
(4) I/O module and intelligent function module manual
Manual name
<manual number (model code)> Description
MELSEC-L CPU Module User's Manual (Hardware Design, Maintenance and
Inspection)
<SH-080890ENG, 13JZ36>
Specifications of the CPU modules, power supply modules, display unit,
branch module, extension module, SD memory cards, and batteries,
information on how to establish a system, maintenance and inspection,
and troubleshooting
MELSEC-L CPU Module User's Manual (Function Explanation, Program
Fundamentals)
<SH-080889ENG, 13JZ35>
Functions and devices of the CPU module, and programming
MELSEC-L CPU Module User's Manual (Built-In Ethernet Function)
<SH-080891ENG, 13JZ37> The built-in Ethernet function of the CPU module
QnUDVCPU/LCPU User's Manual (Data Logging Function)
<SH-080893ENG, 13JZ39> The data logging function of the CPU module
Manual name
<manual number (model code)> Description
MELSEC-Q/L Programming Manual (Common Instruction)
<SH-080809ENG, 13JW10> Detailed description and usage of instructions used in programs
Manual name
<manual number (model code)> Description
GX Works2 Version 1 Operating Manual (Common)
<SH-080779ENG, 13JU63>
System configuration, parameter settings, and online operations of GX
Works2, which are common to Simple projects and Structured projects
GX Developer Version 8 Operating Manual
<SH-080373E, 13JU41>
Operating methods of GX Developer, such as programming, printing,
monitoring, and debugging
Manual name
<manual number (model code)> Description
MELSEC-L I/O Module User's Manual
<SH-080888ENG, 13JZ34> Specifications and troubleshooting of the I/O module

11
Memo

CONTENTS
12
CONTENTS
SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
CONDITIONS OF USE FOR THE PRODUCT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
RELEVANT MANUALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
MANUAL PAGE ORGANIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
TERMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
CHAPTER 1 OVERVIEW 20
CHAPTER 2 EXTERNAL I/O SPECIFICATIONS 22
CHAPTER 3 GENERAL-PURPOSE INPUT FUNCTION 31
CHAPTER 4 GENERAL-PURPOSE OUTPUT FUNCTION 33
CHAPTER 5 INTERRUPT INPUT FUNCTION 35
CHAPTER 6 PULSE CATCH FUNCTION 39
CHAPTER 7 POSITIONING FUNCTION 42
7.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
7.1.1 Procedure for performing the positioning function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
7.2 Connection to External Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
7.2.1 I/O signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
7.2.2 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
7.3 Parameter Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
7.3.1 Positioning parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
7.4 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
7.5 Checking Current Position and Operation Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
7.6 OPR Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
7.6.1 Machine OPR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
7.6.2 Fast OPR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
7.6.3 Forced off of Axis 1 OPR request (SM1842) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90
7.6.4 Precautions on Axis 1 OPR request (SM1842) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90
7.7 Positioning Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
7.7.1 Start of positioning control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
7.7.2 Position control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
7.7.3 Speed/position switching control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98
7.7.4 Current value change. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100
7.7.5 Speed control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
7.8 Multiple Axes Simultaneous Start Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
7.9 JOG Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
7.10 Sub Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
7.10.1 OPR retry function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110
7.10.2 Speed limit function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

13
7.10.3 Speed change function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115
7.10.4 Software stroke limit function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120
7.10.5 Hardware stroke limit function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123
7.10.6 Target position change function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124
7.10.7 Acceleration/deceleration processing function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128
7.10.8 Stop processing function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130
7.11 Absolute Position Restoration Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
7.12 Dedicated Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
7.12.1 Details of dedicated instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
7.12.2 Precautions on dedicated instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161
7.13 Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
7.14 Errors and Warnings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
7.15 Monitoring with a Programming Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
CHAPTER 8 HIGH-SPEED COUNTER FUNCTION 179
8.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
8.1.1 Procedure for performing the high-speed counter function . . . . . . . . . . . . . . . . . . . . . . . . . .181
8.2 Connecting to External Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
8.2.1 I/O signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182
8.2.2 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185
8.3 Parameter Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
8.3.1 Common settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
8.4 Normal Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
8.4.1 Preset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202
8.4.2 Coincidence output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205
8.4.3 Coincidence detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208
8.4.4 Counter function selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211
8.5 Frequency Measurement Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
8.6 Rotation Speed Measurement Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
8.7 Pulse Measurement Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
8.8 PWM Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
8.9 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
8.10 Dedicated Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
8.10.1 Details of dedicated instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242
8.10.2 Precautions on dedicated instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257
8.11 Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
8.12 Errors and Warnings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
8.13 When the LCPU Stops Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
8.14 Monitoring with a Programming Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
APPENDICES 269
Appendix 1 Processing Time of Each Instruction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Appendix 2 Connection Examples with Servo Amplifiers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Appendix 2.1 Connection examples with servo amplifiers manufactured by Mitsubishi . . . . . . . . .271

14
Appendix 2.2 Connection examples with stepping motors manufactured by ORIENTAL MOTOR
CO.,LTD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .273
Appendix 2.3 Connection examples with servo amplifiers manufactured by Panasonic Corporation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .277
Appendix 2.4 Connection examples with servo amplifiers manufactured by SANYODENKI CO.,LTD
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .279
Appendix 2.5 Connection examples with servo amplifiers manufactured by YASKAWA Electric
Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .280
INDEX 281
INSTRUCTION INDEX 284
REVISIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
TRADEMARKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288

15
MANUAL PAGE ORGANIZATION
In this manual, pages are organized and the symbols are used as shown below.
The following illustration is for explanation purpose only, and should not be referred to as an actual documentation.
*1 The mouse operation example (for GX Works2) is provided below.
The section of
the current page is shown.
The chapter of
the current page is shown.
"" is used for
screen names and items.
[ ] is used for items
in the menu bar and
the project window.
shows operating
procedures.
shows reference
manuals.
shows notes that
requires attention.
shows mouse
operations.
*1
shows
reference pages.
shows setting or
operating examples.
Ex.
shows useful
information.
A window selected in the view selection area is displayed.
View selection area
[Online] [Write to PLC...]
Select [Online] on the menu bar,
and then select [Write to PLC...].
Project window [Parameter]
[PLC Parameter]
Select [Project] from the view selection
area to open the Project window.
Menu bar
Ex.
Ex.
In the Project window, expand [Parameter] and
select [PLC Parameter].

16
Pages describing instructions are organized as shown below.
The following illustration is for explanation purpose only, and should not be referred to as an actual documentation.
Descriptions of
setting data and data type
Instruction name
Structure of the instruction
in the ladder mode
shows the devices
applicable to the instruction
Descriptions of
control data (if any)
Execution condition of the instruction
Setting side
User
: Device value is set by the user.
System: Device value is set by
the CPU module.
C
onditions
f
or the error and
error codes
For the errors not described in
this manual, refer to the following.
MELSEC-Q/L Programming
Manual (Common Instruction)
Simple program example(s)
and descriptions of the devices used
Detailed descriptions
of the instruction

17
• Instructions can be executed under the following conditions.
• The following devices can be used.
*1 For details on each device, refer to the following.
MELSEC-L CPU Module User's Manual (Function Explanation, Program Fundamentals)
*2 FX and FY can be used for bit data only, and FD for word data only.
*3 In the "Constant" and "Others" columns, a device(s) that can be set for each instruction is shown.
• The following data types can be used.
Execution condition Any time During on On the rising edge During off On the falling edge
Symbol No symbol
Setting
data
Internal device
(system, user) File
register
Link direct device
J\
Intelligent
function module
device
U\G
Index
register
Zn
Constant
*3
Others
*3
Bit Word Bit Word
Applicable
device*1
X, Y, M, L,
S, M, F, B,
SB, FX, FY
*2
T, ST, C, D,
W, SD, SW,
FD, @
R, ZR U\GZK,H,E,$
P, I, J,
U, D, X,
DY, N,
BL, TR,
BL\S,V
Data type Description
Bit Bit data or the start number of bit data
BIN 16-bit 16-bit binary data or the start number of word device
BIN 32-bit 32-bit binary data or the start number of double-word device
BCD 4-digit Four-digit binary-coded decimal data
BCD 8-digit Eight-digit binary-coded decimal data
Real number Floating-point data
Character string Character string data
Device name Device name data

18
TERMS
Unless otherwise specified, this manual uses the following terms.
Term Description
CPU module The abbreviation for the MELSEC-L series CPU module
Power supply module The abbreviation for the MELSEC-L series power supply module
Branch module The abbreviation for the MELSEC-L series branch module
Extension module The abbreviation for the MELSEC-L series extension module
END cover A cover to be attached to the right side of the rightmost MELSEC-L series module
Display unit A liquid crystal display to be attached to the CPU module
Extension cable The abbreviation for the MELSEC-L series extension cable
LCPU Another term for the MELSEC-L series CPU module
Programming tool A generic term for GX Works2 and GX Developer
GX Works2 The product name of the software package for the MELSEC programmable controllers
GX Developer
Encoder One of the pulse generators that converts input data into binary data (on and off)
Near-point dog
A switch used in positioning systems, placed in front of the starting point of a workpiece When this switch
turns on, the feed speed is switched to creep speed. Therefore, the deceleration time is required while this
switch is on.
Servo on A signal that indicates the normal status of a servo amplifier. A servo amplifier is operable only when this
signal is on.
Servo motor
A motor that rotates according to a command. This motor is highly responsive, therefore frequent and rapid
start and stop are available with high precision.
DC and AC type motors are available. Feedback control is available with the included pulse generator that
detects the number of rotations.
Stepping motor
A motor that rotates by the predetermined angle for every pulse. The number of rotations is proportional to
the number of pulses.
A small power motor is applied, and it rotates accurately without feedbacks. Do not overload the motor,
otherwise it will be out of step.
Zero signal PG0 of a pulse generator (encoder), that is detected once in one rotation
Drive unit (servo amplifier)
A unit used to amplify the power and control the motor in the operation by the positioning function since the
signals, such as pulses, that are output from the CPU module are low voltage and small current.
The unit, also called a servo amplifier, is provided with a servomotor and step motor.
Pulse generator A device that generates pulses. For example, by attaching this device on a motor axis, pulses can be
generated by the rotation of the axis.
Warning Different from an error, a warning is a minor error that does not terminate or stop the operation even if it is
detected.
PWM The abbreviation for pulse-width modulation, a method of changing a ratio of on width to off width of a pulse
wave