Mitsubishi Electric MELSEC FX Series User manual

Programmable Controllers
User's Manual
FX3U-4LC
MITSUBISHI ELECTRIC
MITSUBISHI ELECTRIC
01052010
JY997D39101
Version B
INDUSTRIAL AUTOMATION

(1)
Before installation, operation, maintenance or inspection of this product, thoroughly read through and
understand this manual and the associated manuals. Also, take care to handle the module properly and
safely.
This manual classifies the safety precautions into two categories: and .
Depending on the circumstances, procedures indicated by may also cause severe injury.
It is important to follow all precautions for personal safety.
Store this manual in a safe place so that it can be taken out and read whenever necessary. Always forward it
to the end user.
1. DESIGN PRECAUTIONS
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.
Reference
• Make sure to include the following safety circuits outside the PLC to ensure safe system operation even during
external power supply problems or PLC failure.
Otherwise, malfunctions may cause serious accidents.
1) Above all, the following components should be included: an emergency stop circuit, a protection circuit, an
interlock circuit for opposite movements (such as normal vs. reverse rotation), and an interlock circuit (to prevent
damage to the equipment at the upper and lower positioning limits).
2) Note that when the PLC CPU detects an error, such as a watchdog timer error, during self-diagnosis, all outputs
are turned off. Also, when an error that cannot be detected by the PLC CPU occurs in an input/output control
block, output control may be disabled.
External circuits and mechanisms should be designed to ensure safe machinery operation in such a case.
3) Note that when an error occurs in a relay, triac or transistor output device, the output could be held either on or
off.
For output signals that may lead to serious accidents, external circuits and mechanisms should be designed to
ensure safe machinery operation in such a case.
17
Reference
• Do not bundle the control line together with or lay it close to the main circuit or power line. As a guideline, lay the
control line at least 100mm (3.94") or more away from the main circuit or power line.
Noise may cause malfunctions.
• Ground the shield wire or shield of the shielded cable at one point on the PLC. However, do not ground them at the
same point as the high-voltage lines.
Noise may cause malfunctions.
• Install module so that excessive force will not be applied to the terminal blocks.
Failure to do so may result in wire damage/breakage or PLC failure.
17
Safety Precautions
(Read these precautions before using.)

Safety Precautions
(Read these precautions before using.)
(2)
2. INSTALLATION PRECAUTIONS
3. WIRING PRECAUTIONS
Reference
• Make sure to shut down all phases of the power supply externally before installing.
Failure to do so may cause electric shock or damage to the product. 24
Reference
• Use the product within the generic environment specifications described in PLC main unit manual (Hardware
Edition).
Never use the product in areas with excessive dust, oily smoke, conductive dusts, corrosive gas (salt air, Cl2, H2S,
SO2, or NO2), flammable gas, vibration or impacts, or expose it to high temperature, condensation, or rain and
wind.
If the product is used in such conditions, electric shock, fire, malfunctions, deterioration or damage may occur.
• Do not touch the conductive parts of the product directly.
Doing so may cause device failures or malfunctions.
• Install the product securely using a DIN rail or mounting screws.
• Install the product on a flat surface.
If the mounting surface is rough, undue force will be applied to the PC board, thereby causing nonconformities.
• When drilling screw holes or wiring, make sure that cutting and wiring debris do not enter the ventilation slits.
Failure to do so may cause fire, equipment failures or malfunctions.
• Be sure to remove the dust proof sheet from the PLC's ventilation port when installation work is completed.
Failure to do so may cause fire, equipment failures or malfunctions.
• Connect extension cables securely to their designated connectors.
Loose connections may cause malfunctions.
• Turn off the power to the PLC before attaching or detaching the following devices.
Failure to do so may cause device failures or malfunctions.
- Peripheral devices, display modules, expansion boards and special adapters
- I/O extension units/blocks, FX Series terminal block and the special function units/blocks
- Battery and memory cassette
24
Reference
• Make sure to cut off all phases of the power supply externally before attempting wiring work.
Failure to do so may cause electric shock. 27
Reference
• Connect the AC power supply to the dedicated terminals specified in this manual.
If an AC power supply is connected to a DC input/output terminal or DC power supply terminal, the PLC will burn
out.
• Do not wire vacant terminals externally.
Doing so may damage the product.
• Use class D grounding (grounding resistance of 100 or less) with a wire of 2mm2or thicker on the grounding
terminal of the PLC.
However, do not connect the ground terminal at the same point as a heavy electrical system.
• When drilling screw holes or wiring, make sure cutting or wire debris does not enter the ventilation slits.
Failure to do so may cause fire, equipment failures or malfunctions.
• Make sure to observe the following precautions in order to prevent malfunctions under the influence of noise.
- Do not bundle the power line or twisted shielded cable together with or lay it close to the main circuit, high-
voltage line, or load line.
Otherwise, noise disturbance and/or surge induction are likely to take place. As a guideline, lay the control line
at least 100mm (3.94") or more away from the main circuit, high-voltage line, or load line.
- Ground the shield wire or shield of the shielded cable at one point on the PLC. However, do not use common
grounding with heavy electrical systems.
• Make sure to properly wire to the terminal blocks in accordance with the following precautions.
Failure to do so may cause electric shock, equipment failures, a short-circuit, wire breakage, malfunctions, or
damage to the product.
- The disposal size of the cable end should follow the dimensions described in the manual.
- Tightening torque should follow the specifications in the manual.
27

Safety Precautions
(Read these precautions before using.)
(3)
4. STARTUP AND MAINTENANCE PRECAUTIONS
5. DISPOSAL PRECAUTIONS
6. TRANSPORTATION PRECAUTIONS
Reference
• Do not touch any terminal while the PLC's power is on.
Doing so may cause electric shock or malfunctions.
• Before cleaning or retightening terminals, cut off all phases of the power supply externally.
Failure to do so may cause electric shock.
• Before modifying or disrupting the program in operation or running the PLC, carefully read through this manual and
the associated manuals and ensure the safety of the operation.
An operation error may damage the machinery or cause accidents.
125
141
Reference
• Do not disassemble or modify the PLC.
Doing so may cause fire, equipment failures, or malfunctions.
For repair, contact your local Mitsubishi Electric distributor.
• Turn off the power to the PLC before connecting or disconnecting any extension cable.
Failure to do so may cause equipment failures or malfunctions.
• Turn off the power to the PLC before attaching or detaching the following devices.
Failure to do so may cause equipment failures or malfunctions.
- Peripheral devices, display modules, expansion boards and special adapters
- I/O extension units/blocks, FX Series terminal block and the special function units/blocks
- Battery and memory cassette
125
141
Reference
• Please contact a certified electronic waste disposal company for the environmentally safe recycling and disposal of
your device. 17
Reference
• The PLC is a precision instrument. During transportation, avoid impacts larger than those specified in the general
specifications of the PLC main unit manual.
Failure to do so may cause failures in the PLC.
After transportation, verify the operations of the PLC.
17

(4)
MEMO

1
FX3U-4LC User's Manual
FX3U-4LC
User's Manual
Foreword
This manual describes the FX3U-4LC temperature control block and should be read and understood before
attempting to install the hardware.
Store this manual in a safe place so that you can take it out and read it whenever necessary. Always forward
it to the end user.
© 2010 MITSUBISHI ELECTRIC CORPORATION
Manual number JY997D39101
Manual revision B
Date 5/2010
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.

2
FX3U-4LC User's Manual
Outline Precautions
• This manual provides information for the use of the FX3U-4LC temperature control block.
The manual has been written to be used by trained and competent personnel. The definition of such a
person or persons is as follows;
1) Any engineer who is responsible for the planning, design and construction of automatic equipment using
the product associated with this manual should be of a competent nature, trained and qualified to the
local and national standards required to fulfill that role. These engineers should be fully aware of all
aspects of safety with aspects regarding to automated equipment.
2) Any commissioning or maintenance engineer must be of a competent nature, trained and qualified to the
local and national standards required to fulfill the job. These engineers should also be trained in the use
and maintenance of the completed product. This includes being familiar with all associated manuals and
documentation for the product. All maintenance should be carried out in accordance with established
safety practices.
3) All operators of the completed equipment should be trained to use that product in a safe and coordinated
manner in compliance with established safety practices. The operators should also be familiar with
documentation that is connected with the actual operation of the completed equipment.
Note: the term 'completed equipment' refers to a third party constructed device that contains or uses the
product associated with this manual.
• This product has been manufactured as a general-purpose part for general industries, and has not been
designed or manufactured to be incorporated in a device or system used in purposes related to human life.
• Before using the product for special purposes such as nuclear power, electric power, aerospace, medicine
or passenger movement vehicles, consult with Mitsubishi Electric.
• This product has been manufactured under strict quality control. However when installing the product
where major accidents or losses could occur if the product fails, install appropriate backup or failsafe
functions into the system.
• When combining this product with other products, please confirm the standards and codes of regulation to
which the user should follow. Moreover, please confirm the compatibility of this product with the system,
machines, and apparatuses to be used.
• If there is doubt at any stage during installation of the product, always consult a professional electrical
engineer who is qualified and trained in the local and national standards. If there is doubt about the
operation or use, please consult the nearest Mitsubishi Electric distributor.
• Since the examples within this manual, technical bulletin, catalog, etc. are used as reference; please use it
after confirming the function and safety of the equipment and system. Mitsubishi Electric will not accept
responsibility for actual use of the product based on these illustrative examples.
• The content, specification etc. of this manual may be changed for improvement without notice.
• The information in this manual has been carefully checked and is believed to be accurate; however, if you
notice any doubtful point, error, etc., please contact the nearest Mitsubishi Electric distributor.
Registration
• The company name and the product name to be described in this manual are the registered trademarks or
trademarks of each company.

3
FX3U-4LC User's Manual
Table of Contents
SAFETY PRECAUTIONS .................................................................................................. (1)
Standards................................................................................................................................... 7
Certification of UL, cUL standards ....................................................................................................... 7
Compliance with EC directive (CE Marking) ........................................................................................ 7
Associated Manuals.................................................................................................................. 9
Generic Names and Abbreviations Used in the Manual ...................................................... 11
Reading the Manual ................................................................................................................ 13
1. Introduction 14
1.1 Outline........................................................................................................................................... 14
1.1.1 Major features of the FX3U-4LC .................................................................................................... 14
1.2 External Dimensions and Part Names .......................................................................................... 15
1.3 Terminal Layout ............................................................................................................................ 16
1.4 Power and Status LEDs ................................................................................................................ 16
2. Specification 17
2.1 General Specifications .................................................................................................................. 18
2.2 Power Supply Specifications......................................................................................................... 18
2.3 Performance Specifications .......................................................................................................... 18
2.4 Input Specifications ....................................................................................................................... 19
2.4.1 Temperature input specifications................................................................................................... 19
2.4.2 Measurement precision ................................................................................................................. 20
2.4.3 Current detector (CT) input specifications ..................................................................................... 20
2.5 Input Type ..................................................................................................................................... 21
2.6 Output Specifications .................................................................................................................... 21
3. System Configuration 22
3.1 General Configuration ................................................................................................................... 22
3.2 Applicable PLC.............................................................................................................................. 23
3.3 Connection with PLC..................................................................................................................... 23
4. Installation 24
4.1 DIN rail Mounting .......................................................................................................................... 25
4.2 Direct Mounting ............................................................................................................................. 26
5. Wiring 27
5.1 Power Supply Wiring..................................................................................................................... 28
5.1.1 Power supply wiring....................................................................................................................... 28
5.1.2 Grounding...................................................................................................................................... 28
5.2 Input Wiring ................................................................................................................................... 29
5.2.1 Wiring example of thermocouple................................................................................................... 29
5.2.2 Wiring example of resistance thermometer ................................................................................... 29
5.2.3 Wiring example of micro voltage input........................................................................................... 30
5.3 Output Wiring ................................................................................................................................ 31
5.4 Terminal Screw and Tightening Torque........................................................................................ 32

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FX3U-4LC User's Manual
6. Introduction of Functions 33
6.1 Functions List ................................................................................................................................ 33
6.2 Control Mode Switch Function ...................................................................................................... 34
6.3 Transistor Output Selection Function............................................................................................ 36
6.4 PID control .................................................................................................................................... 38
6.4.1 Easy PID control with two degrees of freedom.............................................................................. 38
6.4.2 Overshoot prevention function....................................................................................................... 39
6.5 Two-position Control ..................................................................................................................... 40
6.6 Heating/cooling PID control........................................................................................................... 41
6.6.1 Heating/cooling PID control ........................................................................................................... 41
6.6.2 Overshoot prevention function....................................................................................................... 42
6.6.3 Overlap/dead band function .......................................................................................................... 43
6.6.4 Cooling method ............................................................................................................................. 44
6.7 Cascade control ............................................................................................................................ 45
6.7.1 Cascade control............................................................................................................................. 45
6.7.2 Tuning during cascade control ...................................................................................................... 47
6.7.3 SV tracking selection function ....................................................................................................... 48
6.8 Auto Tuning Function .................................................................................................................... 49
6.8.1 AT (Auto tuning) ............................................................................................................................ 49
6.8.2 Conditions for performing and aborting AT (auto tuning) .............................................................. 51
6.8.3 AT (auto tuning) bias ..................................................................................................................... 53
6.9 Startup Tuning Function................................................................................................................ 54
6.9.1 ST (startup tuning)......................................................................................................................... 54
6.9.2 Conditions for performing and aborting ST (startup tuning) .......................................................... 56
6.10 AUTO/MANUAL mode changeover ............................................................................................ 58
6.10.1 AUTO mode and MANUAL mode................................................................................................ 58
6.10.2 Balance-less, bump-less function................................................................................................ 59
6.11 Heater Disconnection Alarm Function (HBA).............................................................................. 60
6.11.1 Heater disconnection alarm function ........................................................................................... 60
6.11.2 Number of times of heater disconnection alarm delay ................................................................ 61
6.12 Loop Breaking Alarm Function (LBA).......................................................................................... 62
6.12.1 Loop breaking alarm function ...................................................................................................... 62
6.12.2 Loop breaking alarm dead zone (LBD)........................................................................................ 64
7. Alarm 65
7.1 Alarm List ...................................................................................................................................... 65
7.2 Alarm Functions ............................................................................................................................ 67
7.2.1 Upper limit input value alarm ......................................................................................................... 67
7.2.2 Lower limit input value alarm ......................................................................................................... 67
7.2.3 Upper limit deviation alarm ............................................................................................................ 68
7.2.4 Lower limit deviation alarm ............................................................................................................ 68
7.2.5 Upper/lower limit deviation ............................................................................................................ 68
7.2.6 Range alarm .................................................................................................................................. 69
7.2.7 Alarm wait operation...................................................................................................................... 69
7.2.8 Alarm re-wait operation ................................................................................................................. 70
7.3 Alarm Dead Zone Setting.............................................................................................................. 71
7.4 Number of Times of Alarm Delay .................................................................................................. 72