Maintenance Management of your company's PLC (Programmable Logic Controller).

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• What is a PLC?
• How many PLCs is your bottom line depending on?
• Do you have an up to date list of all PLC model types, part availability, program copies, and details for your company?
• Do you have at least one trained person per shift, to maintain and troubleshoot your plant PLCs?
• Does your maintenance personnel work with PLCs following written company or corporate policy, and procedures?
  

If you could not answer with confidence or you answered ‘No’ to any of the above questions, you need to read this article on maintenance management of PLCs. Why? Because the PLCs (Programmable Logic Controllers) are the brains of your operation. When the PLC is not functioning properly, lines shut down, plants shutdown, even city bridges and water stations could cease to operate. Thousands to millions could be lost by one little PLC in an electrical panel that you never even knew existed. But most importantly, damage to machine and personnel could result from improper maintenance management of your company’s PLCs.
What is a PLC?
First I’d like to explain in the most non-technical terms possible, What a PLC is. As this article is not just for the maintenance technician, but for maintenance managers, plant managers and corporate managers. A PLC (Programmable Logic Controller) is the type of computer that controls most machines today. The PLC is used to control AND to troubleshoot the machine. The PLC is the brain of the machine. Without it, the machine is dead. The maintenance technicians we train, are the brain surgeons. That is how I explain it to my doctor any way. (His mouth drops open, “... you train brain surgeons?”)
Important Note: Just as a doctor asks the patient questions to figure out what is wrong, a maintenance technician asks the PLC questions to troubleshoot the machine. The maintenance technician uses a laptop computer to see what conditions have to be met in order for the PLC to cause an action to occur (like turn a motor on). In a reliable maintenance management environment, the maintenance technician will be using the PLC as a troubleshooting tool to reduce downtime.
A little more detailed definition of a PLC: A programmable controller is a small industrial strength computer used to control real world actions, based on its program and real world sensors. The PLC replaces thousands of relays that were in older electrical panels, and allows the maintenance technician to change the way a machine works without having to do any wiring. The program is typically in ladder logic, which is similar to the wiring schematics maintenance electricians are already accustomed to working with. Inputs to a PLC can be switches, sensors, bar codes, machine operator data, etc. Outputs from the PLC can be motors, air solenoids, indicator lights, etc.
How many PLCs is your bottom line depending on?
My company has had an ongoing PLC related global maintenance survey since the year 2000. The majority of the participants back in 2001, reported 3-6 PLCs in their facility, that they know of. Granted most participants are managers and don't open electrical panels much, but many of the participants are from fortune 500 companies having hundreds of employees. The odds are most of them have 12-30 PLCs in their facilities. Currently the average is 6-9 reported, so the good news is the industry as a whole is becoming more PLC aware.
It is common to only learn about a PLC once the machine is down and the clock is ticking at a thousand dollars an hour, or more. Unfortunately, it is also common that after the fire is out, it's on to the next fire, without fully learning what can be done to avoid these costly downtimes in the future, and in other similar machines in a company or corporation.
Some older electrical panels may only have relays in them, but most machines are controlled by a PLC. A bottleneck machine in your facility may have a PLC. Most plant air compressors have a PLC. How much would it cost if the bottleneck or plant air shut down a line, a section of your facility, or even the entire plant?
Do you have an up to date list of all PLC model types, part availability, program copies and details for your company?
The first step to take is to perform a PLC audit. Open every electrical panel, and write down the PLC brand, model, and other pertinent information. Then go the next two steps. Analyze the audit information and risk, then act on that analysis. To help you out, I want to share with you our company PLC audit form.

Collected Information	Recommended Action
Machine or Area Name	Ex: warehouse conveyor, pump station 3, Strapper 2, Line 7, Traffic signal west main, etc.
PLC Program Name	Ex: 1789GAA1, P3, Strap2, 5872443, WestMainTL, etc.
Network Node Address	No two addresses will be the same. Ex: 2, 3, 17, 21
Network Name	Common to be same as Program name, but not mandatory.
PLC Brand	Ex: Allen Bradley, Siemens, Schneider, Mitsubishi, DirectSoft, Omron
PLC Model Number	Ex: PLC-5/25, SLC-504, SIMATIC S5, MELSEC FX1N, DL 405
Is Spare Available	Yes on shelf, or only in less critical machines or no
Date Program Last Backed Up	Make program backups part of your semiannual PM program
Discriptored Copy of program available	Without discriptored copy of program, troubleshooting and downtime are greatly increased.
Does PLC have EEPROM	Or other method of storing backup program in a chip on PLC
Last date Program Changed	Remember to log when outside consultants or OEM make program changes too.
Last date EEPROM Burned	Should be saved to EEPROM (Burned) after every successful program change.
Date battery last changed	See manufacturer’s data for recommended change frequency.
Other information you may need	Might be facility location when corporate HQ is using this form.

Once you have collected the basic information in your Plant wide and/or corporate audit, you need to analyze the information to develop an action plan based on risk analysis. In the risk analysis, bottlenecks and other factors will help you assess priorities. Starting with the highest priority PLC, you will need to ask more important questions.

• Do we have the most common spares for the PLC?
• Is the OEM (Original Equipment Manufacturer) available 24/7? Or even in business any more?
• Do we have a back up copy of the PLC program?
• Does our program copy have descriptions so we can work with it reliably and efficiently?
• Do we have the software needed to view the PLC program? Are our maintenance personnel trained on that PLC brand?

These are some of the questions our managers must ask, to avoid unnecessary risk and to insure reliability.
Do you have at least one trained person per shift to maintain and troubleshoot your plant PLCs?
Is your maintenance staff trained on the PLC? (Silly to squander over a couple thousand in maintenance training when the lack of PLC knowledge could cost you 10 thousand an hour. ... or worse. I can give you a couple good reasons why you should have at least one trained person per shift, to work reliably with PLCs. You do not want to see greater downtime on off shifts because the knowledge base is on day shift only. Also with all the baby boomers (our core knowledge base in the industry) about to retire, it is not smart management to place all your eggs in one basket.
Then the question should be asked, what should we look for in training. Well I have been training individuals for over a decade and could easily write another article on just PLC training alone. I can tell you here, that you should seek training with two primary objectives.
1. The training you decide on, should stress working with PLCs in a Safe and Reliable way. (not just textbook knowledge or self learned knowledge)
2. Secondly, the training should be actually centered around the PLC products you are using or plan to use in your facility.
I feel the two criteria above are the most important. Some other good ideas to get more out of your PLC training investment would be to get hands on training using the actual PLC programs and software the maintenance technician will be working with in the facility. Insure your personnel have the software, equipment and encouragement to continue with self education. PLC Training CBT (Computer Based Training) CDs are a great way for employees to follow up 6 months after the initial training. Some other ideas you could do is to provide them with simulation software and/or a spare PLC off the shelf to practice with.
Does your maintenance personnel work with PLCs following written company or corporate policy and procedures?
It seems that in our industrial culture, if policy and procedures are not written and enforced, we eventually stray back to the old unreliable ways. I have reviewed many policy and procedures as well as books on the topic matter and hardly ever see maintenance management of the PLCs included. It amazes me how an organization can write guidelines for what they believe is the health of the entire organization’s body, and leave out the brain (the PLC :>). Once again, a complete PLC policy and procedure manual is out of the scope of this article. However, I will donate a few random items below to get you started.

1. Write PLC policies and procedures into your existing maintenance policy and procedures. (SOP)
2. All personnel working with PLCs will be trained on that PLC equipment.
3. Backup copies of the PLC programs will be made every 6 months regardless of change status.
4. If a PLC program has been changed ...
   • It will be documented in the software copy, in the printed copy and in the CMMS program.
   • Copies of the PLC program will be stored on a media more reliable than floppy disk (CD, USB, etc.).
   • Multiple copies will be stored on laptop, maintenance manager’s office and off site (corporate).
   • If available, EEPROM will be updated with new changed program.
   • If outside vendor changes, a-d will be performed by maintenance personnel
5. Future equipment purchases ...
   • A common PLC brand in all equipment will be sought out (Standardization of PLC types)
   • OEM will be required to provide a descriptor copy of PLC programs in the customer’s native language.
   • All PLC 110v control voltage will have a line filter on it.
   • All PLCs will have the backup EEPROM option for zero downtime in some failure modes.
6. Forcing inputs and outputs on or off shall be treated as a Safety issue. (See safety SOP)
7. Inputs and outputs shall not be forced on or off with out a clear understanding of complete effect on PLC program and a second opinion.
   • If forces are installed, they shall be removed with in 24 hours and a more permanent solution found.
   • All forces should be documented in software and a written log before being enabled.
8. Online programming is somewhat of a safety risk, normal procedure is to change offline and download to the PLC.

Hope this helps, if you have a specific question you can find me in the PLC discussion area at the PLC Discussion Forum.
Don Fitchett (President)
Business Industrial Network
PLC Training - The best for less
www.bin95.com

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Sekilas tentang PLC

PLC (Programmable Logic Controller)

The PLC has come a long way from its development in the seventies, whilst their speed will never match that of the PC but who wants a 3GHz PLC, its overall reliability, customization and ability to work under virtually any conditions around the world make the PLC the only choice when process control is required.

While the PLC is without doubt the number one choice in process control, this doesn't mean it is without problems there are two areas that have caused some problems for engineers. The first problem was that the original concept back in the seventies was to develop a device that could be easily and quickly programmed, so Ladder logic was developed to make it familiar to the electrical engineer, however over the years PLC's were being supplied by several major names such as: Allen Bradley - Omron - Siemens - Mitsubishi - Square D, and here the problem was created, each of them developed their own style of Ladder logic.

For developers this meant learning several different styles of programming and also how to use the differing development tools, while the developer could cope with this, a large number of maintenance engineers found it very difficult. I personally know one international company that has 3 different PLC's and the maintenance engineers only know one and they struggle with that one, the lack of control within the company means the company downtime and efficiency is far below what it could be.

The second problem is new, PLC's have to be robust to survive the industrial environment, the designs up till 2001 were very well suited and also lent themselves to rapid replacement of faulty modules, however some PLC designers have now developed PLC's where the surface area of plastic is only 50%, this is easily damaged, and during assembly into racks small metal objects such as screws can fall into the sensitive electronics.

Also gone is the backplane that allowed rapid replacement, now modules have to be slotted together, so if the middle one fails you have to strip the PLC down. Finally the miniature size causes wiring problems, the engineers I know tend to have fingers the size of bananas, so you can imagine the fun they have in rack assembly.

Despite these little drawbacks, the PLC is still far better than the PC, which has more the two failings one of which tends to be the Operating System.

· Rockwell - a US product. Their Logix Platforms supply the end user with everything necessary to build a reliable application in control integration from Control to Drive to HMI Logix, operating over both Open and Proprietary networks.

Allen Bradley PLC

· Omron - extensively used throughout Europe and Far East. They have extended their range of PLC's with the new CJ1 series for total machine control. The CJ series is set to replace the very popular and reliable C200H alpha series. Program development is via Omron's Cx Programmer, the latest version is v6.0, replacing the dated Syswin ver3.4.

Omron PLC


Siemens, European product. For many years Siemens PLC's have been amongst those at the top, with safety, reliability and flexibility as their selling points.The Simatic range is very extensive and can provide an overall solution to process and machine control. Cost is expensive but then you are paying for a good product, however licensing and their custom programming laptop I consider too much, paying several thousand pounds against Omron and Mitsi few hundred pounds. Support is vital and if you are unfamiliar with the product then support is a priority.

Siemens PLC

Mitsubishi now have the FX3u series PLC, a more powerful and higher performance PLC.
It is very flexible and modular, allowing it to be expanded up to 384 IO, with instructions being processed in 0.065usec. Communicating via Profibus and Ethernet. Further details on this can be found via LC Automation and their INFORMATION ZONE.

Mitsubishi provide an extensive range of products from PLC's to Drives, Robots and HMI's and most importantly their overall customer support is good. The PLC development tool is GxDeveloper, this superceded Medoc, GX Developer is a bit dated, however they now have available GXiec, which is a very good development package, allowing you to create programs based upon IEC61131.
GXiec in our opinion is very good.

Mitsubishi PLC

Keyence The world's smallest PLC with AC power supply built-in. Easy-to-use Access Window, Compact operator interface panel available. Fast processing with 10-µs interrupt and 30-kHz high-speed counters. Complete with User-friendly Windows® ladder logic software.

Keyence PLC

 

Typical PLC Control System

 

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Handbook of instrumentation and controls

MODUL 1 TEMPERATUR DETECTOR

RESISTANCE TEMPERATURE DETECTORS (RTDs)
Temperature
RTD Construction

THERMOCOUPLES
Thermocouple Construction
Thermocouple Operation

FUNCTIONAL USES OF TEMPERATURE DETECTORS
Functions of Temperature Detectors
Detector Problems
Environmental Concerns .

TEMPERATURE DETECTION CIRCUITRY
Bridge Circuit Construction
Bridge Circuit Operation
Temperature Detection Circuit
Temperature Compensation
MODUL 2 PRESSURE DETECTORS
PRESSURE DETECTORS
Bellows-Type Detectors
Bourdon Tube-Type Detectors
Summary
PRESSURE DETECTOR FUNCTIONAL USES
Pressure Detector Functions
Detector Failure
Environmental Concerns

PRESSURE DETECTION CIRCUITRY
Resistance-Type Transducers
Inductance-Type Transducers
Capacitive-Type Transducers
Detection Circuitry
MODUL 3 LEVEL DETECTORS

LEVEL DETECTORS
Gauge Glass
Ball Float
Chain Float
Magnetic Bond Method
Conductivity Probe Method
Differential Pressure Level Detectors

DENSITY COMPENSATION
Specific Volume
Reference Leg Temperature Considerations
Pressurizer Level Instruments
Steam Generator Level Instrument

LEVEL DETECTION CIRCUITRY
Remote Indication
Environmental Concerns
MODUL 4 FLOW DETECTORS

HEAD FLOW METERS
Orifice Plate
Venturi Tube
Dall Flow Tube
Pitot Tube .

OTHER FLOW METERS
Area Flow Meter
Displacement Meter
Hot-Wire Anemometer
Electromagnetic Flowmeter
Ultrasonic Flow Equipment

STEAM FLOW DETECTION

FLOW CIRCUITRY
Circuitry .
Use of Flow Indication
Environmental Concerns
MODUL 5 POSITION INDICATORS

SYNCHRO EQUIPMENT
Synchro Equipment

SWITCHES
Limit Switches
Reed Switches

VARIABLE OUTPUT DEVICES
Potentiometer
Linear Variable Differential Transformers (LVDT)
Summary
POSITION INDICATION CIRCUITRY
Environmental Concerns
MODUL 6 RADIATION DETECTORS
OBJECTIVES
RADIATION DETECTION TERMINOLOGY
Electron-Ion Pair
Specific Ionization
Stopping Power
Summary
RADIATION TYPES
Alpha Particle
Beta Particle
Gamma Ray
Neutron .

GAS-FILLED DETECTOR
Summary
DETECTOR VOLTAGE
Applied Voltage
Summary
PROPORTIONAL COUNTER
MODUL 7 PROCESS CONTROLS

PRINCIPLES OF CONTROL SYSTEMS
Introduction
Terminology
Automatic Control System
Functions of Automatic Control
Elements of Automatic Control
Feedback Control

CONTROL LOOP DIAGRAMS .
Terminology
Feedback Control System Block Diagram
Process Time Lags
Stability of Automatic Control Systems

TWO POSITION CONTROL SYSTEMS
Controllers
Two Position Controller
Example of Two Position Control
Modes of Automatic Control .

PROPORTIONAL CONTROL SYSTEMS
Control Mode
Proportional Band
Example of a Proportional Process Control System

RESET (INTEGRAL) CONTROL SYSTEMS
Reset Control (Integral)
Definition of Integral Control
Example of an Integral Flow Control System
Properties of Integral Control

PROPORTIONAL PLUS RESET CONTROL SYSTEMS
Proportional Plus Reset
Example of Proportional Plus Reset Control
Reset Windup

PROPORTIONAL PLUS RATE CONTROL SYSTEMS
Proportional-Derivative
Definition of Derivative Control
Example of Proportional Plus Rate Control
Applications

PROPORTIONAL-INTEGRAL-DERIVATIVE CONTROL SYSTEMS
Proportional-Integral-Derivative
Proportional Plus Reset Plus Rate Controller Actions

CONTROLLERS
Controllers
Control Stations
Self-Balancing Control Stations

VALVE ACTUATORS
Actuators
Pneumatic Actuators
Hydraulic Actuators
Electric Solenoid Actuators
Electric Motor Actuators

download : pdf1 pdf2 (Please right click and Save As...)

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Siemens Simatic Step7 Professional Edition 2006 SR5 Multilanguage ISO

Siemens Simatic Step7 Professional Edition 2006 SR5 Multilanguage ISO | 800 MB

STEP 7 Professional is the programming and configuring software designed for professional use with SIMATIC controllers.

It supports the user through all the stages of a development process for automation solutions, such as

 Installation and management of projects
 Configuring and parameter assignment of hardware and communications
 Symbol management
 Program generation for SIMATIC S7 target systems
 Loading programs on target systems
 Testing the automation plant
 Plant fault diagnostics

STEP 7 Professional consists of the following:

 The STEP 7 basic package including the well proven LAD, FBD and STL languages
 S7-GRAPH for graphic programming of sequential controls
 S7-SCL, the high-level language for programming even the most complex tasks
 S7-PLCSIM for off-line simulation of an automation solution.

STEP 7 Professional includes all the programming languages complying with the international IEC 61131-3 standard and therefore enables cross-company standardization and helps save high software engineering overheads. STEP 7 Professional permits both programming of the PLC-based SIMATIC S7 and C7 controllers and the controllers for PC-based automation, SIMATIC WinAC. This gives the user freedom of choice when selecting a hardware platform and the opportunity to use hybrid software configurations.

STEP 7 Professional executes under the MS Windows 95/98/Me/NT 4.0/XP Professional operating systems and is adapted to the graphics and object-oriented functionality.

Netload

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Siemens Simatic Step7 Professional SR4 | 1 GB
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If you work for business, Please buy this software... OK!

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Aplikasi Robotic Di Pabrik Otomotif

Automation System

Aplikasi tangan-tangan robot di pabrik otomotif. Bagaimana tangan robot tersebut bisa bekerja. Jawaban Dengan penerapan dan implementasi sistem otomatisasi PLC & SCADA mesin ini bekerja. Selanjutnya.... Lebih banyak baca buku, lebih banyak tahu.

Factory robotic automation is based on the application of computers. It involves various technologies. These technologies are applied by persons highly qualified in automation engineering. The technologies involves in factory automation are motor control and drive system, machine vision system, programmable logic control system and manufacturing executive systems. These are also known as automation tools without which automation is not possible.


robotic automationFactory robotic automation facilitates creativity and perspective to implement robot technology. It makes many manufacturing processes possible without human interference. Automation integrates logic, power, information technologies and process into one drive system. Automaton applied in the factory uses machine vision system. It uses robotic machine handling process to perform identification, orientation and decoding tasks. The programmable logic control system one the important automation tools facilitates the successful implementation of the automation control system


The robotic palletizer is capable of producing an infinite variety of robotic palletizing patterns. The patterns are driven by your shipping needs and can be varied based on the product being palletized. There is need to unify the business with plant floor system in the present global scenario. The factory automation makes it possible. It also provides flow of information to instruct people and machines to deliver the product as per requirement.

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Persentasi Software Baru RSLOGIX5000 V17

Berikut ini persentasi mengenai software terbaru dari Rockwell RSLogix5000 V17. Semoga bermanfaat.



Jika ingin melihat lebih jelas silahkan klik http://docs.google.com/Presentation?id=dcsqcp9z_198tfnfqkdr

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Programmable Logic Controllers Oleh W. Bolton

This is the introduction to PLCs for which baffled students, technicians and managers have been waiting. In this straightforward, easy-to-read guide, Bill Bolton has kept the jargon to a minimum, considered all the programming methods in the standard IEC 1131-3 - in particular ladder programming, and presented the subject in a way that is not device specific to ensure maximum applicability to courses in electronics and control systems.

Now in its fourth edition, this best-selling text has been expanded with increased coverage of industrial systems and PLCs and more consideration has been given to IEC 1131-3 and all the programming methods in the standard. The new edition brings the book fully up to date with the current developments in PLCs, describing new and important applications such as PLC use in communications (e.g. Ethernet an extremely popular system), and safety in particular proprietary emergency stop relays (now appearing in practically every PLC based system).

The coverage of commonly used PLCs has been increased, including the ever popular Allen Bradley PLCs, making this book an essential source of information both for professionals wishing to update their knowledge, as well as students who require a straight forward introduction to this area of control engineering.

Having read this book, readers will be able to:
* Identify the main design characteristics and internal architecture of PLCs
* Describe and identify the characteristics of commonly used input and output devices
* Explain the processing of inputs and outputs of PLCs
* Describe communication links involved with control systems
* Develop ladder programs for the logic functions AND, OR, NOT, NAND, NOT and XOR
* Develop functional block, instruction list, structured text and sequential function chart programs
* Develop programs using internal relays, timers, counters, shift registers, sequencers and data handling
* Identify safety issues with PLC systems
* Identify methods used for fault diagnosis, testing and debugging programs

Fully matched to the requirements of BTEC Higher Nationals, students are able to check their learning and understanding as they work through the text using the Problems section at the end of each chapter. Complete answers are provided in the back of the book.

* Thoroughly practical introduction to PLC use and application - not device specific, ensuring relevance to a wide range of courses
* New edition expanded with increased coverage of IEC 1131-3, industrial control scenarios and communications - an important aspect of PLC use
* Problems included at the end of each chapter, with a complete set of answers given at the back of the book

Rincian lebih lanjut

Programmable Logic Controllers: an introduction

Oleh W. Bolton

Diterbitkan oleh Newnes, 2006

ISBN 0750681128, 9780750681124

304 halaman

Baca? Klik DISINI!

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