Category Archives: PLC Applications

What is a DCS?

DCS stands for “Distributed Control System” which is an automated control system that streamlines the functionalities of the different devices used throughout a work space. DCS utilizes a wide range of controllers to permit all the parts to converse with one another just as PCs do. These controllers are distributed geographically across a plant to allow for high-speed communication to the control process. When utilizing various kinds of modules, the framework may require diverse correspondence norms, for example, Modbus and Profibus.

Learn the difference between a Distributed Control System (DCS) and a Programmable  Logic Controller (PLC) here: PLC vs. DCS: What’s the difference? – MRO Blog

Components of a DCS

A distributed control system or DCS is a control system in which the controller components are not local but are dispersed throughout the system with every component sub-system controlled by one or more controllers. The entire arrangement of controllers is associated by systems for correspondence and observing. DCS is an extremely wide term utilized in an assortment of enterprises, to monitor and control hardware. Below is a list of places that use Distributed Control Systems.

  • Radio signals
  • Dry cargo and bulk oil carrier ships
  • Electrical power grids and electrical generation plants
  • Traffic signals
  • Water management systems
  • Oil refining plants
  • Chemical plants
  • Sensor networks
  • Environmental control systems

History of the DCS

The first Distributed Control System was made by Honeywell in 1969. This new design depended on a vast distributed control to the computer modules. Every one of these modules controlled a few different processors, for the most part, one to four. They were associated with a high-speed data communications link, known as a data highway which made communications between each of the computer modules and the central operator console possible. This plan permitted the administrator to monitor the activity of every local process. 

Moving forward, microprocessor-based modules replaced hardwired computer modules in the 1970’s. However, Today’s distributed control systems are much more powerful and faster than the early systems because of advancements in microprocessors and other electronic circuits. The next section of this blog illustrates how a present DCS operates and is shown in the diagram below.

DCS Operation “ The Three Qualities”

A DCS has three main qualities. The first quality is the conveyance of different control capacities into little arrangements of subsystems, which are of semiautonomous, and are interconnected through a rapid correspondence transport. A portion of these capacities incorporate securing information, information introduction, process control, process supervision, revealing data, and the saving and recovery of data.

The second trait of DCS is the computerization of assembling processes by coordinating propelled control techniques. Furthermore, the third quality of the DCS is organizing the entire process as a system. A DCS sorts out the whole control structure as a solitary computerization system where different subsystems are brought together through an appropriate order and data stream.

These qualities of the DCS are shown in the figure below. The essential architecture in a DCS include engineering workstation, operating station or HMI, process control unit or local control unit, smart devices, and a communication system.

Important Features of a DCS

  1. HMI: A DCS can monitor and control through HMI’s, otherwise known as a Human Machine Interface, which gives adequate information to the administrator to charge over different procedures which acts as the center of the system. However, this type of industrial control system covers large areas whereas a DCS covers one region. A DCS uses the whole process plant to control the process as a PC window. Trending, logging and graphical representation of the HMI’s give effective user interface. A Powerful alarming system of a DCS helps operators to respond more quickly to the plant’s shape when needed. 
  2. Security: Access to control the various processes leads to plant safety. The DCS design offers a perfect and secure system to handle framework functions for top notch factory automation control. Security is also provided at different levels such as an operator level, engineer level, and an entrepreneur level.
  3. The handling of complex procedures: APLC or Programmable Logic Controller is utilized to control and monitor the procedure parameters at a rapid speed. Click here for more information about PLCs. However, a DCS is preferred for more complex control applications because with a higher number of I/O’s with dedicated controllers, it is able to handle such processes. These are used in assembling processes where the structuring of various products is in multiple procedures such as a batch process control.

Considerations When Choosing a DCS

The bulk of control system decisions include the use of a programmable logic controller (PLC) or a distributed control system (DCS). In some cases one alternative is clearly better for a plant while the choice is not as simple in others. Selecting the control system entails several considerations that will help the customer meet their short-and long-term goals.

Difference between PLC and DCS systems: A PLC is an industrial computer that is built to control manufacturing processes such as robots, high-speed packaging, bottling, and motion control. In the last 20 years, PLCs have gained functionality and provide benefits for small plant applications. PLCs are usually solitary islands of automation that can be unified so they can communicate with one another. PLCs are great for smaller applications that are unlikely to expand in the future. 

A DCS distributes controllers throughout the automation system and offers a standard guidance, automated monitoring, a systemwide database, and easy-to-share information. DCSs are commonly used in process applications and larger plants, and are easier to maintain throughout the plant’s life cycle for large device applications.

The Application type determines the platform: PLCs and DCSs are typically suited to one of two forms of production: discrete manufacturing and process manufacturing. Discrete manufacturing facilities, which typically use PLCs, consist of separate manufacturing units which generally assemble components, such as labeling or fill-and-finish applications. Facilities for process manufacturing typically use DCSs, automate continuous and batch processes and enforce formulations consisting of components rather than parts. Process manufacturing facilities calculate their production in bulk. DCS automation is used by large continuous process installations, such as refineries and chemical plants.

Several aspects must be considered when finding the right DCS such as:

  • Process size
  • Integration needs
  • Functionality
  • High availability
  • Expansion or modification plans
  • ROI on the facilities lifespan

What is a PLC?

A Programmable Logic Controller, abbreviated as “PLC” is a computer used to address the issues of a particular assembling process. These devices come in a wide range of shapes and sizes, with numerous alternatives for computerized and simple I/O, as well as protection from high temperatures, vibration, and electrical noise. The invention of the PLC allows for computers to be streamlined into the industrial automation process.

A PLC can be a solitary device figuring and executing operations, or a rack of various modules utilized to meet whatever your automation system requires. A portion of the extra parts include processors, power supplies, additional IO, interfaces, and more. Each part cooperates to have the option to run open or shut circle activities that are appraised at fast and high accuracy. Take a CNC machine for instance; a PLC would be utilized to control positioning, motion, and torque control. These devices are popular since they are inexpensive in relation to the amount of power and lifespan they possess. PLCs can run for hours on end. 

The diagram below displays the process of a Programmable Logic Controller system.

History of PLCs

Programmable Logic Controllers (PLCs) first hit the scene in the late 1960s. The essential purpose behind planning such a device was eliminating the high cost required to replace the complicated relay based control systems for major U.S. vehicle makers. There was a primary issue and that was that they were mechanical. This implies that they wear out and must be replaced from time to time. Additionally, relays take up too much room. These, alongside different contemplations, prompted the advancement of PLCs. More enhancements to PLCs happened during the ’70s. In 1973 the ability to communicate between PLCs was introduced. This made it possible to have the controlling circuit perform at a distance from the machine it was controlling. In several cases, the absence of institutionalization in PLCs caused a few different issues. This was improved in the 1980s. The size of PLCs was additionally decreased, which meant plants were utilizing space much more effectively. The ’90s expanded the assortment of manners by which a PLC could be modified such as block programs and a guidance list. They also observed PLCs being replaced by PC’s in a few cases. Be that as it may, PLCs are still being used in a wide range of businesses, and it’s going to remain that way in the foreseeable future.

How It Works “The Three Tasks”

The way a PLC works is very straightforward: The PLC receives data from associated sensors or information devices, processes the information, and triggers outputs dependent on pre-customized parameters. 

Depending on the inputs and outputs, a PLC can monitor and record run-time data such as machine productivity or operating temperature, automatically start and stop processes, generate alarms if a machine malfunctions, and that’s just the beginning. Programmable Logic Controllers are a versatile and powerful control arrangement, adaptable to practically any application.

A PLC essentially performs three tasks: a PLC checks the information inputs, goes through the program, and changes the outputs. Then, it circles back to the top and starts once more. This appears incredibly straightforward, however, it tends to be made very complex with various sources of I/O. The scan time is the time it takes for the PLC to experience the three fundamental tasks. This time is significant, as it influences how rapidly the inputs of info can be read. The sources of info should be on or off long enough for the PLC to read them. On the off chance that they are not on that long, issues begin to occur. Luckily, there are approaches to fix this issue. Perhaps the most ideal way is to utilize an interrupt at whatever point an input goes to high. This will guarantee that the PLC doesn’t miss the change.

Inputs and Outputs (I/Os)

As we’ve seen up until this point, inputs and outputs are very important to the activity of a PLC. Two key components to consider in picking the privilege PLC are the quantity of I/Os and their location. Since PLC controls undergo a large process, you will need to ensure it can deal with various I/Os. The quantity of both analog and discrete devices that your system has will affect this choice too. Remember that the quantity of I/Os will likewise decide the size of your PLC’s body. The location of I/Os will also have an effect on your choice. Will your framework require a local I/O, or will you need both local and remote I/Os? Subsystems are needed to answer these questions sufficiently. Keep in mind that the speeds and distance at which your PLC operates is important for this.

PLC Acronyms Worth Knowing

These acronyms will help you better understand what exactly you are looking for.

ASCIIAmerican Standard Code for Information Interchange
BCDBinary Coded Decimal
CSACanadian Standards Association
DIODistributed I/O
EIAElectronic Industries Association
EMIElectroMagnetic Interference
HMIHuman Machine Interface
IECInternational Electrotechnical Commission
IEEEInstitute of Electrical and Electronic Engineers
I/OInput(s) and/or Output(s)
ISOInternational Standards Organization
LLLadder Logic
LSBLeast Significant Bit
MMIMan Machine Interface
MODICONModular Digital Controller
MSBMost Significant Bit
PIDProportional Integral Derivative (feedback control)
RFRadio Frequency
RIORemote I/O
RTURemote Terminal Unit
SCADASupervisory Control And Data Acquisition
TCP/IPTransmission Control Protocol / Internet Protocol

What to Consider When Buying a PLC

  • Will the framework be powered
  •  by AC or DC voltage? 
  • Will the system be situated in one spot or spread out over a huge region?
  • Does the system run quick enough to meet my application’s necessities? 
  • What kind of programming is utilized to program the PLC? 
  • Whenever required by your application, can the PLC handle simple data inputs and outputs, or perhaps a mix of both? How am I going to speak with my PLC? 
  • Do I need to arrange availability and would it be able to be added to my PLC? 
  • Will the PLC have the option to deal with the quantity of information inputs and outputs that my application requires? 
  • Does the PLC have enough memory to run my user program? 
  • Inputs and Outputs (I/Os)

Looking To Buy?

Check out our collection of PLCs at the link “Showing PLC”  below. We provide you with the thousands of Program Logic Controllers by the brands Schneider Electric, SIEMENS, and Yaskawa at the best prices. Below are just a few PLC devices we have for sale on our website. Please visit and contact us if you have any questions.  Showing PLC.

PLC vs. DCS: What’s the difference?

Before we get into the differences of a PLC’s and DCS’s, we need to talk about what each of them are designed to do.

What is a PLC?

A PLC, or Programmable Logic Controller, is a computer that has been adapted to specifically meet the needs of any specific manufacturing process. These devices come in many different shapes and sizes, with many options for digital and analog I/O, as well as protection from high temperatures, vibration, and electrical noise. The invention of the PLC allowed computers to be streamlined into the industrial automation process.

A PLC can be a single device calculating and executing operations, or a rack of different modules may be used to meet whatever your automation system requires. Some of the additional components include processors, power supplies, additional IO, interfaces, and much more.  Every part works together to be able to run open or closed loop operations that are rated at high speed and high precision. Take a CNC machine for example; a PLC would be used to control positioning and motion, as well as torque control. These devices are popular because they are very inexpensive relative to the amount of power and how many hours you get out of them.

 What is a DCS?

A Distributed Control System is an automated control system that streamlines the functionalities of the various devices that are used throughout an entire work space. This type of system uses many different controllers to allow all the machining parts to talk to each other as well as computers that can input parameters and display information such as power usage, speed, and much more. These controllers are distributed geographically across a plant to allow for high-speed communication to the control room. When using different types of modules however, the system may require different communication standards such as Modbus and Profibus. DCS’s started coming to fruition throughout the 1960’s once the microcomputer was brought widespread into the market.

Then what exactly is the difference?

A PLC will probably be used to control a machine that isn’t too complex wheres the DCS can have total control of all the operations in an entire plant. The PLC is preferred in situations where the machine does not have to worry about meeting specific conditions inside the plant. These conditions typically involve operations that may need to stop or restart, as well maintaining precise temperatures. A DCS will be able to take advantage of all the aspects of an automated system, from the machines and sensors to the controllers and computers. An entire DCS is much more expensive than a few PLC’s, but each have their advantages in any given situation and certain automated systems will always require one over the other.

Visit MRO Electric and Supply’s website to see all of our available Programmable Logic Controllers. If we don’t have what you need listed on the site, contact us at sales@mroelectric.com or (800)691-8511 and we will be happy to help.

Modicon PLC History

Modicon PLC History

Modicon PLC History

Richard E. Morley, also known as Dick, was an American electrical engineer. He was an employee at Bedford and Associates, located in Massachusetts. He is most commonly known for his involvement with the production of the first Programmable Logic Controller (PLC) for General Motors and the Modicon in 1968. General Motors Company, often referred to as GM, is an American multinational corporation that is headquartered in Detroit, Michigan that engineers, manufactures, markets and distributes vehicles and vehicle parts and sells financial services.

Known as an author, educator, influencer and specialized engineer, Morleys’ accomplishments and contributions have earned him numerous awards from families such as ISA (the instrumentation systems and automation society), Inc. Magazine, Franklin Institute, SME (the Society of Manufacturing Engineers), and the Engineering Society of Detroit. SME offers the Richard E. Morley Outstanding Young Manufacturing Engineer Award for outstanding technical accomplishments in the manufacturing space by engineers age 35 and younger.

Schneider Electric currently owns the Modicon brand of PLCs. The PLC has been recognized as a major advancement in the automation space and has had an unprecedented impact on the manufacturing community as a whole. PLCs were designed to replace re-wiring and hard-wired control panels with software program changes when production updates were necessary. Before PLCs came about, several relays, drum sequencers, cam timers and closed-loop controllers were used to manufacture vehicles and vehicle parts. Re-wiring the relays and other necessary components was a very in-depth and costly process, but clearly worth the effort. The Modicon 084 PLC was modeled to be programmed in ‘ladder logic’ which had the look of the schematic diagrams of relay logic it was replacing.  This made the transition to PLCs easier for engineers and other professionals in the manufacturing space.  The automotive industry is still one of, if not the largest users of PLCs today. MRO Electric and Supply has new and refurbished Modicon parts available including the Modicon Quantum series. We also offer repair pricing. For more information, please call 800-691-8511 or email sales@mroelectric.com.

The Modicon PLC Timeline

A few years later, in the 1970’s, dialogue between PLCs came about. Introduced as the first industrial communications network, Modbus was based on a Slave/Master architecture that used messaging to communicate between Modbus nodes. All and all, a lacking standardization made PLC communications a nightmare.

In the  1980’s, General Electric made an effort to regiment the interconnection of devices from several manufacturers with MAP (manufacturing automation protocol). PLC programming software was also created to operate on personal as well as professional computers in order to remove the need for dedicated programming terminals or handheld programmers.

As years have gone on, PLCs have evolved as technology evolves. Nowadays, they include process, motion, and distributed control systems, as well as complex networking. Equivalent to an average, run-of-the-mill desktop computer, PLCs have capacities for data handling storage and impressive processing power.

PLC Security

plc security

PLC Security

Programmable logic controllers, also known as PLCs, initially came about in the late 1960s. PLCs were designed to replace relay-based machine control systems in the major U.S. vehicle manufacturing space. The relay-based control systems were considered hard to use and were disliked amongst those in the automation and manufacturing in.

In 1968, Dick Morley of Bedford Associates in Massachusetts designed the Modular Digital Controller, later dubbed the Modicon. After the Modicon 084’s initiation into the world, there was no looking back to those relay-based control systems. Be sure to check out our article covering Modicon PLC history to learn more.

PLCs are user-friendly microprocessor-based specialty computers that carry out control functions, many of which are of high levels of complexity. They are engineered to endure harsh and strenuous situations such as in heated, cooled and even moist environments. Used for automation usually in the industrial electromechanical space, PLCs are computers that deal with the controlling of machinery, often on  the following:

  • factory assembly lines
  • power stations
  • distribution systems
  • power generation systems
  • gas turbines

PLCs are programmed using a computer language. Written on a computer, the program is then downloaded to the PLC via a cable. These programs are stored in the PLCs memory. The hard-wired logic is exchanged for the program fed by its user during the transition between relay controls to PLC. The manufacturing and process control industries have gotten to take advantage of PLC applications-oriented software since Modicon PLCs inception.

plc security
PLC Functions and Directions

PLCs use programmable memory in order to store particular functions and directions. Some functions and directions would include:

  • on control
  • off control
  • timing
  • sequencing
  • counting
  • arithmetic
  • data manipulation
PLC Types

Understanding the different types of PLCs will be very helpful when looking into PLC security.

The numerous types of PLCs can be organized into three principal categories:

  • Advanced PLC: Advanced PLCs offer the greatest processing power out of all of the PLC types. They feature a larger memory capacity, higher input/output (I/O) expandability, and greater networking options.
  • Compact Controller: Logic Controllers are increased intermediate level offerings with an increased set of instructions and a greater input/output (I/O) than a run-of-the-mill logic controller
  • Logic Controler: A logic controller is often referred to as a ‘smart relay’. They are generally straightforward to use and considered a good place to begin when becoming acquainted with PLCs. They are cost-effective for low input/output (I/O), slower speed applications.
PLC Security

As security concerns remain in many professional spaces including the factory automation space, becoming up-to-speed with the different types of PLC Security is imperative. By creating and implementing an effective strategy to remain secure, you will likely avoid issues, downtime, and setbacks. Understanding the different types of PLCs will be very helpful when looking into PLC security.

PLC Cybersecurity: How the control network is linked to the internet, as well as other networks. A handful of PLC issues could likely involve the following:

  • Incident response planning and plans;
  • Issues drafting and reviewing policies
  • Issues drafting and reviewing procedures
  • Retention of cybersecurity experts and vendors;
  • A need for preparation of a breach:
    • exercises
    • training
    • breach simulations
  • A need for cybersecurity insurance review and counseling
  • A demand for record management and information infrastructure;
  • Privacy risk management
  • Assessment of cybersecurity risk in mergers and acquisitions;
  • Payment Credit Industry (PCI) Compliance protocols
  • Vendor contract management protocols
  • Supply chain risk management

PLC Physical Security: Although PLC physical security differs from PLC cybersecurity, it is still important and should be prioritized when an individual or a company is undergoing breach simulations, training, and exercises. PLC physical security deals with:

  • correcting default passwords
  • ensuring only certified individuals are in the control system’s environment
  • limiting access to thumb drives and securing access

MRO Electric and Supply maintains a comprehensive stock of Modicon PLC parts, including the Modicon Quantum series. Also, feel free to check out our repair and core exchange programs to learn how to save.

Understanding Issues with Security
In order to create and implement training and procedures for staff, you must understand how issues with security occur.  Not all cybersecurity attacks occur from external hackers or scammers. In fact, experts believe that only an estimated 20% of all cybersecurity attacks are intentional and intended to be malicious. Whether you think it’s possible or not, an offended employee could indeed be your hacker. Almost always caused by software issues, device issues, and malware infections, cybersecurity seems straight-forward initially, until you dig into those fine, often overlooked details.

As many in the automation space may know, PLC cybersecurity wasn’t a thing a decade ago. These days, PLCs are connected to business systems through any run-of-the-mill network and aren’t separated from other networks that other automation equipment may also be on.  As time goes on, it’s becoming more and more common to see TCP/IP networking from a business system standpoint. By connecting via TCP/IP, data exchange, as well as more rational and scalable business decisions, is enabled.

PLC Security Factors:
  • Although it may not actually connect to the internet, a control system is unsafe. Contrary to popular belief, a modem connection could also experience intrusion and a hack.
  • Wireless networks, laptop computers, and trusted vendor connections could be other sources of connections in which people may be likely to overlook.
  • Keep in mind that the majority of IT departments are unaware of factory automation equipment, including CNCs, CPUs, PCBs, robotics parts and, last but not least, PLCs.
  • Piggybacking off of the last point, IT departments’ lack of experience with the aforementioned equipment, along with their lack of experience with industrial standards and scalable processes indicate that they should not be in-charge and responsible for a company’s PLC security. Nobody wants an annoyed employee to make inappropriate changes to a PLC’s communication highway.
  • Hackers do not necessarily need to understand PLC or SCADA to block PC-to-PLC communication. They absolutely do not need to understand a PLC or SCADA system to cause operational or programming issues.
  •  Often times, control systems, including ones that many PLCs integrate with, use Microsoft Windows, which is very popular amongst hackers.
  • Some PLCs crash simply by pinging an IP address, like what happened at the Brown’s Ferry Nuclear Plant, which is located in upstate Alabama. Since the incident in 2006, the plant has undergone numerous security, operational, and management improvements.

In conclusion, when a security breach occurs, regardless of the specifics, understanding that time is of the essence will help smooth over most incidents. Trusting who has access to a control systems environment and thumb drive is crucial. If someone has access to the control system environment and thumb drive, ensure they’re well-qualified and up-to-speed with their team and/or company.

Choosing the most appropriate PLC

PLC

Choosing the most appropriate PLC

As many machine automation professionals know, deciding on which PLC to work with can be one of the most difficult decisions you have to make when organizing your control system.  There is no one size fits all equation, so are here are some guidelines I use.

Brand –   Many of the major players such as have small, medium, and large-scale PLCs.  Always consider when brands the end user already is using.  Things will always go smoother if the maintenance personnel is already accustomed to the brand of PLC you choose.  Also, try to pick a brand that will have stellar local support for the end user if you are not in the area.

Sizing – Sizing a PLC is imperative to the success of your project.  If you go too small,  you may max out your I/O (such as this Modicon Quantum I/O)on changes and additions.  On the other hand, if you go too large,  you may blow go over your budget. Leaving room for expansion is ideal, but, in the long run, going over your budget is not practical.

  • Count up your:
    • Discrete input points
    • Discrete output points
    • Analog input points
    • Analog output points
  • Communications.   regularly have a port available on the PLC to communicate with it from your laptop without disconnecting other devices.  With modern PLCs with several communications methods, there is no reason for this to happen.
    • Will you need remote I/O?  This can reduce installation time and troubleshooting in the long term.
    • Will your system utilize an HMI?  How will you communicate with it?
    • Having a way to remotely monitor your PLC is becoming standard practice.

MRO Electric and Supply has new and refurbished Omron and Siemens products available. We also offer repair pricing. For more information, please call 800-691-8511 or email sales@mroelectric.com.

plc

How to maintain a PLC (Programmable Logic Controller)

Updated: March 2020

Why is PLC Maintenance Important?

PLCs (programmable logic controllers) are such an integral part of the automation world, and in turn a major contributor to the industrial market. Downtime can be incredibly costly, and finding parts for legacy units can be difficult and time consuming. (MRO Electric sells many legacy and discontinued automation components, from top brands) Therefore, properly maintaining your PLC can avoid unnecessary headaches and get the most life out of your units.

Pre-Maintenance Checklist

Before starting preventative maintenance on your PLC, make sure to do the following:

  1. Back up your PLC program prior to getting your hands dirty (it’s also a good idea to always keep a master copy of operating programs on hand).
  2. Follow proper lockout/tagout procedures.
  3. Remove power from the system. Power should always be off and unplugged during maintenance.
  4. Audit all parts in use.

PLC Maintenance Procedures

This is a good guidebook to use when performing preventive PLC maintenance:

  1. Check environmental factors / operating conditions. Humidity, temperature and other factors play an important role in the longevity and proper operation of your components. Be sure that these factors are consistently within the range of your PLCs optimal operating conditions.
  2. Clear debris, dust, and buildup from your units. A clean working environment for your PLC is a great way to prevent downtime. Also, dust getting to the circuit boards could cause a catastrophic short circuit.
  3. Clean or replace all filters installed in enclosures. This allows your PLC to get the maximum airflow and ensures consistency.
  4. Check all your connections for a tight fit, especially I/O modules. This is a very simple way to make sure everything is working smoothly. Also, a loose connection may cause lasting damage to your components.
  5. Inspect I/O devices for proper adjustments.
  6. Check LED battery indicators on the RAM memory module in the CPU. If the OK LED is on or flashing, replace the battery ASAP.

Other Things to Keep in Mind

  1. Calibrate circuit cards with process control analogs every 6 months.
  2. Service devices such as sensors every month.
  3. Never place other pieces of equipment that produce lots of noise or heat close to your PLC.

How to maintain a PLC (Programmable Logic Controller)

As many of us know, PLCs (programmable logic controllers) are staples in the factory automation world. In order to have them running optimally and as efficiently as possible, routine maintenance is imperative. Generally, manufacturers produce PLCs to endure strenuous, unsterilized environments. By adhering to an adequate maintenance schedule, PLCs operating timeframe can be lengthened.

Protect your PLC

Always be on the lookout for corrosive and conductive contaminants that have the potential to become a detriment to a PLCs’ components. By completing visual inspections for black dust and blowing airborne particles from the PLC’s vicinity, you are lowering the likelihood of contamination.

Is power flowing?

A PLC will not operate correctly without adequate power. To avoid any operation bugs, remain vigilant of any surges or shorts.

Calibrate Analog Components

Always refer to the preventative maintenance schedule for any analog input device. Analog inputs need to be cleaned regularly and calibrated as accurately as possible.

Take EMI into consideration

EMI (electromagnetic interference) is known to cause horrible issues for PLCs without clearly indicating what the specific issue is or how to go about fixing it. To remain ahead of the game, many perform an audit of the local wiring to pinpoint potential EMI sources before they interfere with the operation of your PLC. Lower-level components and high-current wires often interfere with each other, which wiring designs must take into consideration.

Additional PLC Maintenance Tips

By creating a PLC maintenance checklist and adhering to it strictly, operating errors can likely be avoided. The space between the PLC and the machine it’s controlling should be minimal.

MRO Electric and Supply has new and refurbished Modicon PLC parts available here. We also offer repair pricing. For more information, please call 800-691-8511 or email sales@mroelectric.com.

Schneider Electric / Modicon PLC and HMI Batteries

Schneider Electric / Modicon PLC and HMI Batteries

MRO Electric and Supply has new and refurbished Schneider Electric and Modicon Quantum parts available now, and also offers repair pricing. For more information, please call 800-691-8511 or email sales@mroelectric.com.

Schneider Electric / Modicon PLC and HMI Batteries

Product Line Model Type Part Number Manufacturer
Quantum
140CPUxxxxx
Lithium 3V
990XCP98000
Duracell (DL2/3A)
(soldered connector)
Quantum 140XCP90000 Lithium 990XCP99000
Quantum
141MMS42501
Lithium 3V
990XCP98000 or Duracell (DL2/3A)
43502625 (soldered connector)
Quantum
141MMS53502
Lithium 3V
990XCP98000 or Duracell (DL2/3A)
43502625 (soldered connector)
Compact PC-O984-xxx Lithium 3.6V (long) “O” 60-0576-000 Eternacell (T04/41)
Compact
PC-A984-1xx
Lithium 3.6V (short) “A”
60-0576-100
Saft (LS3)
PC-E984-2xx Maxell (ER3STC)
Momentum
172xNN2xx2
Lithium 3.6V
170XTS15000
Tadiran (TL-5955)
PNN PV:03
JNN PV:01
Momentum 172xNN2xxx2 Alkaline “AAA” Commercially Available
Modicon Micro
110CPUx1x0x
Lithium 110XCP98000 Duracel (DL2/3A)
Capacitor 110XCP99000 (soldered connector)
Modicon 984 AM-C986-003
(2 cell pack)
MA-9255-000
Modicon 984 AM-C986-004
Modicon 984 AM-M907-1xx
Modicon 984 AM-M909-0xx
Modicon 984 AM-C921-xxx 60-0490-000
Modicon 984 PC-L984-x8x
Lithium 3.6V “AA”
60-0515-000
Eternacell (T06141)
Modicon 984 PC-O984-x8x Maxell (ERGC#5)
Modicon 984 PC-E984-x8x Saft (LS6)
Modicon 984 PC-O984-455 Tadaran (TL-5104)
Modicon 984 PC-O984-351
Modicon 984 AM-C986-004
Modicon 984 AM-C996-80x
Modicon 984 PC-M984-23x
Modicon 984 AS-B984-1xx
Modicon 984 AM-S929-00x
Lithium
MA-8234-000
Modicon 984 AS-B885-00x
Modicon 984 AM-O984-ATX 60-0490-000
Modicon 984 Rechargeable (Qty. 2) 60-0610-000
Modicon 984 100-865 (Qty. 3) 60-0595-000
Modicon 984 AM-O984-MCX 60-0582-000
Modicon 884
Modicon 884
AS-884A-xxx
MA-8234-000
AS-J890-x0x
Modicon 584 AS-506P-xxx Lithium (3 card) MA-0147-001
Modicon 584 AS-509P-xxx Lithium (4 card) MA-0147-002
Modicon 584 AS-M507-00x 60-0481-000
Modicon 584
3 Card Battery Pack
Lithium AS-5284-001
Alkaline AS-5284-002
Modicon 584
4 Card Battery Pack
Lithium AS-5378-002
Alkaline AS-5378-001
Modicon 484
Lithium MA-0147-001
Alkaline 60-0286-000
Modbus Multiplexer
Modbus Multiplexer NW-0278-000 60-0549-000
0085/0185 (Sharp)
0085/0185 (Sharp)
(with connector) PA-0254-000 Sharp
(without connector) PA-0493-000 (UBATN-5001-SCZZ)
Symax
Symax
Model 400
Lithium 3.6V “AA”
60-0515-000 Eternacell (T06141)
Model 450 29576-03688 Maxell (ERGC#5)
Model 600 (SqD Part #) Saft (LS6)
Model 650 Tadaran (TL-5104)
PS25
PS35
8052 MCM713
Symax
PS20/21
Alkaline “D”
Commercially Available
PS30/31
PS50/51
PS60/61
Symax
8005 Model 50
Ram Memory Pack
8005 MP1
8005 MP4
Symax
PS20
Battery Holder
29904-08200
(SqD Part#)
Symax
SCP1xx 8020 SMM115
8040 PCM-110 (SqD Part #)
Symax
M100
29904-08960
(SqD Part #)
Symax
8009 Compact
Lithium 3V (Type BA1)
Sanyo (CR12600SE)
TDI Battery Co. (?)
Otte Controls
(DUNT-521NCZZ)
Symax
Symax 20
8884 SBP20
(SqD Part #)
PanelMate
PanelMate
all models
60-0627-000
Maxell
60-0628-000
PanelMate PM0632400 (Qty. 3) 60-0595-000
PanelMate PA-0285-000
PanelMate MA-024M-000
Telemecanique
TSX Premium TSXP57xxx Lithium 3.6V “1/2 AA” TSXPLP01 Saft (LS3)
TSX Micro TSXP37xxx Single TSXPLP101 Maxell (ER3STC)
TSX Micro Ten Pack
TSX Micro
TSXMRPxxxxx
Lithium 3V “Button” TSXBATM01
Panasonic (BR2325)
Single TSXBATM101
10 Pack
CCX17
TCCX17xxx
Lithium 3.6V “1/2 AA” TSXPLP01 Saft (LS3)
Single TSXPLP101 Maxell (ER3STC)
Ten Pack
FTX117
TFTXRSMxxxxx
Lithium 3V “Button” TSXBATM01
Panasonic (BR2325)
Single TSXBATM101
10 Pack
TSX 17
Lithium 3.6V “1/2 AA”
TSX17ACC1
Saft (LS3)
Maxell (ER3STC)
(Soldered Connectors)
XBTKN
Lithium 3.6V “1/2 AA”
TSX17ACC1
Saft (LS3)
XBTKM Maxell (ER3STC)
(Soldered Connectors)
Series 7
TSX 27xx
2.6 V
AZ1 AQ 0006
2.4 Volt with minimum of 110 mAH
TSX P471x/P472x Shrink-wrapped cells
TSX RAM xx 8 Soldered on board
TSX AXM 162
TSX AXM 171xx/182
TSX SCM 2xxx
UC TSX 27
Series 7
TSX P473xx/P474xx 3.6V
AZ1 AQ 0002
3.6 Volt with minum of 110 mAH
TSX P67xxx Shrink-wrapped cells
TSX 76 x Soldered on board
TSX P871/P872/P874xx
TSX P76 x
TSX P107xxx
TPMX P474xx
TPMX P674xx
TPMX874xx
TPMX P1074xx
TSX T407 x
TSX RAM xxx 16
TSX MEM 4x
TSX P87 30/310 3.6V (Qty. 3)

TSX PLCs – Compact, Flexible, Cost-Effective

TSX PLCs
TSX Nano PLCs are easy to set up and have numerous built in functions, such as memory for storing programs, battery-backed RAM, and real-time clocks for modules with 16 and 24 I/O’s. They can be installed easily on a mounting rail or base plate in the vertical or horizontal position. TSX PLCs are programmed in lists of instructions using the FTX 117 programming terminal, in Ladder or Instruction list language using software on an FT 2000, FTX 517 terminal or PC compatible. They can be used to augment extendable TSX PLCs using a single extension per base. Depending on the model they have

16 I/O : 9 inputs + 7 outputs
24 I/O : 14 inputs +10 outputs.

The following types of inputs and outputs are used:

Inputs : 24 Volts
Outputs : Relay outputs for models with ~ 100… 240 Volt power supply, transistor outputs with positive logic for models with 24 Volt power supply.

I/O Extension

Each TSX Nano base PLC can be extended using an I/O extension. This extension is created by one of the PLCs with 10, 16, or 24 i/o. The function of each PLC is defined by the position of the coding selector switch:
Position 0 : base PLC
Position 1 : I/O extension

Peer PLCs

Up to 3 peer TSX PLCs, communicating via common words, can be connected to the base PLC. In this case, only the base PLC can receieve an I/O extension. The function of each PLC is defined by the position of the coding selector switch. I/O addressing of peer PLCs is identical to that of the base TSX PLC. The extension link cable between the base PLC and PLC extensions is shielded, twisted pair  and is no more than 200 meters long.  Each PLC has 2 reserved (IW) and 2 reserved (QW) words for exchanging data between PLCs. These exchange words are updated automatically. For each PLC, the user program is only able to write to the 2 %QW output words and read the 2 %IW input words.

MRO has many Modicon PLCs available. For more information, please email sales@mroelectric.com or call 1-800-691-8511.

140CPU43412A Error Codes and Hot Standby

Our previous blog post on the 140CPU43412A describes the 140CPU43412A Configuration and Setup. 

140CPU43412A Hot Standby

You cannot create a Quantum Hot Standby configuration running one 140CPU53414A PLC with Unity firmware and one with NxT firmware. When using an NxT configuration in hot standby, both PLCs must have NxT firmware. When using a Unity Quantum hot standby configuration, only specific hot standby controllers can be used. The 140CPU43412A and 140CPU53414A PLCs are not supported in Unity Hot Standby configurations.

140CPU43412A Error Codes

The following are the error codes for the 140CPU43412A:

140CPU43412A Error Codes
140CPU43412A Error Codes

140CPU43412A Error Codes
140CPU43412A Error Codes

140CPU43412A Error Codes
140CPU43412A Error Codes

For ordering info or for a 140CPU43412A price quote you can call 1-800-691-8511 or email sales@mroelectric.com.