Why PLCs fail!


Boulting Technology has released an infographic to help engineers mitigate problems with programmable logic controller (PLC) based control systems. The handy guide highlights the top five causes of failure and can be downloaded, free of charge, from their news page.boulting_plc_failure_paperPLC-based control systems are invaluable to a manufacturing or processing business because they control and regulate critical production systems and processes. A failed control system can cause significant plant downtime and is likely to be extremely costly; it can also create a hazardous situation when the system is controlling a critical process. By following correct maintenance procedures, businesses can minimise the chances of system failure, which in turn increases productivity, minimises costs and helps to maintain a valuable business reputation.

Faults with PLC input/output (I/O) modules and field devices account for 80 per cent of system failures. Usually, fixing these types of issues is relatively straightforward; however diagnosing them requires a basic knowledge of the system and on occasion specialist test equipment such as a multimeter. In addition, more often than not some form of PLC software diagnosis can aid with identifying the root cause of the fault. Although diagnosing the fault can often be time-consuming and requires specialist knowledge and experience, rectifying it can be as simple as replacing an I/O module or reconfiguring a field device.

Other common causes of failure include environmental issues, the integrity of the system earth, power supplies, failure of battery back-up during a power outage, electromagnetic or radio frequency interference and network and communication problems.

“Understanding the main causes of PLC control system failure means engineers can do more to prevent them,” explained James Davey, service manager of Boulting Technology. “In most cases, the minute a control system fails a business starts to lose money through downtime and missed deadlines. At worst it can result in a hazardous situation that needs immediate attention. Simple steps, such as regular control system health-checks, backing up PLC software and planning for contingency in the event of a power outage helps keep production processes up and running.

“At Boulting Technology, we pride ourselves on our ability and experience to use planned maintenance to prevent problems before they occur. Similarly, our guide to PLC control system failure will help plant engineers look out for warning signs of a failing system and take action before the issue becomes severe.”

@BoultingTech #PAuto #PLC

Switches in critical control networks in petrochem plant!



Unipetrol is a major refinery and petrochemical company in the Czech Republic. One of the company’s biggest assets is the industrial premises Chempark Záluží which is the largest chemical production facility in the country. The facility is currently the seat of several dozens of important chemical and service companies and is a daily workplace for 6,500 employees from 180 companies.

The part of the plant where Ethylene is produced is particularly important since it is widely used as a component in many other products produced at the plant. A stoppage in the Ethylene production would have enormous economic implications because it would affect the overall production. A complete new network backbone for power control and distribution as well as an upgraded network backbone for the emergency shutdown system has been built with Westermo switches to support the applications in the Ethylene unit.

The communication infrastructure and the systems has been built and implemented by Inelsev, a Czech company that provides services for industrial automation and energetic systems. The decision to use Westermo devices was based on a strong working relationship between Inelsev and Westermo’s Czech distributor.

Pavel Ješina with one of the Westermo RedFox switches.

Pavel Ješina with one of the Westermo RedFox switches.

“This is a plant where reliability is absolutely crucial. The systems are designed to be extremely robust in order to guarantee continuous operation and to protect the plant and the people who work here. In the previous network solution, we used another switch brand that we had to replace. The main reason for that was the network ring recovery time. Whenever the network had to recover, it took so long that connected equipment (OPC servers) would not start up and connect properly. WeOS powered Westermo products, including the ring network protocol FRNT with 20 ms recovery time, was a perfect fit. Extremely fast, robust and easy to use,” said Pavel Ješina, R&D manager at Inelsev, who has designed and implemented both networks.

The two networks were built in 2011. The emergency shutdown system was an upgrade project where old switches from another brand were replaced with Westermo Lynx switches in a dual ring network topology. The purpose of this network is to shut down the plant in an emergency situation. The power control and distribution network was built as a completely new system and connects 30 substations throughout the plant with a central control room. The network consists of 270 communication devices, over 500 process screens and panels, 13,000 I/O connections and more than 300,000 alarms. The network consists mainly of Lynx L210-F2G and a variety of RedFox industrial switches.

The many combinations of ports and the possibility to mix copper and fibre media was another big driver for selecting Westermo products. “Inside a building we can use regular copper Ethernet cables, but the cables connecting the different buildings must be fibre due to safety legislations,” explained Pavel. “The many models and port combinations in the RedFox Industrial range allowed us to select the ideal product at every location and to prepare for expanding the network in the future.”

Another positive outcome from using Westermo devices is that configuration and maintenance is extremely simple. All managed Westermo devices are powered by the same operating system, WeOS. This means that you will get an identical experience whether you configure a Lynx, RedFox or any other managed Westermo device, regardless of model. It also means that any new functionality added to any new WeOS version will be backwards compatible and available in any previously installed WeOS device. The operating system is designed to be as robust as the hardware. It is made to be simple to use and configure and thoroughly tested in the Westermo software test lab. “I have worked with many different brands of switches and routers, and compared to many others, configuring a Westermo switch is like kindergarten,” said Pavel.

To make configuration and maintenance even simpler, the company also provides WeConfig, a “Made Easy” network configuration management tool designed to simplify both the initial configuration and network commissioning which can be performed much quicker than before and over the lifetime of a network hundreds of man hours can be saved. “I use WeConfig for upgrading the Westermo devices when a new firmware upgrade is made available. The tool makes upgrades simple and hassle free and I can access all units from one central point and automated updates are performed swiftly and securely. I am excited to start experimenting more with WeConfig when we expand our network.

“We have created a straightforward, robust and reliable network solution. This is exactly what is needed here and the Westermo units have been working flawlessly since they were installed. The products are easy to use and I would not hesitate to select Westermo products for another application where the same type of requirements are needed,” he concluded.

 @westermo_global #CzechR #PAuto

Preparing pharmaceutical and medical technology for the future.


Production environment requirements in the pharmaceutical and medical technology sectors are very high and producers need to keep abreast of current industry trends. Such trends include; process optimisation for the purpose of increasing overall equipment effectiveness (OEE), effective asset life cycle management and predictive maintenance using enterprise mobility and intelligent solutions (smart apps). Increasing networking along with the use of automation technology in accordance with Industry 4.0 have paved the way for these developments.

Industry 4.0
The Internet of Things has found its way into production in the form of Industry 4.0: increasingly networked systems with more communication-capable components have meant an ever-increasing volume of data. Thanks to “big data”, production is being made more and more intelligent, with the pinnacle of achievement being the smart factory. The key to success lies in determining the right information from the mass of data available, analysing the data and drawing findings from them. The aim of such Smart Data Management is to optimise the plant in question and prepare it for the future in terms of site operational excellence.

Robots are increasingly taking on handling tasks to reduce human effort in the medical/pharma sectors, for example by supplying filled syringes to the end-of-line packaging station.

Robots are increasingly taking on handling tasks to reduce human effort in the medical/pharma sectors, for example by supplying filled syringes to the end-of-line packaging station.

In addition, overall equipment effectiveness (OEE) has developed into an obvious trend. The main factors that have contributed towards this have been optimised plant utilisation and productivity for which manufacturing execution systems (MES) and enterprise resource planning (ERP) are of vital importance. Interfaces such as the MES interface from Mitsubishi Electric enable data to be collected quickly and easily at plant level and transferred to higher-level MES or ERP systems at the control level for further analysis. OEE can be specifically optimised based on the results without the need for a gateway PC to transfer the data. Based on the System Q PLC from Mitsubishi Electric the MES interface can be configured by a plant engineer in just around 15 minutes.

Cost control strategies look for a more compact design, shorter production cycles and substantially minimised waste. Automation technologies strongly support these approaches with robot technology in particular being used to achieve these aims.

Collaboration between Robots and Humans
Today’s pharmaceutical and medical technology production environments see robots and human operators increasingly working side by side. Mitsubishi Electric’s integrated Robot Safety Solution helps manufacturers to boost productivity and lift human-machine collaboration by allowing the robot to continue operation, within tight constraints, while operators access its work cell. Safety sensing technology detects movements in two predefined zones within the operating environment of the manufacturing cell and transmits the information to the SafePlus safety system. A reduced operating speed or a movement stop is then assigned to the robot in real time, thus enabling operators to work in close proximity to the moving robot without a safety cage. As a result, humans and robots are able to work within an environment where the risk of danger is eliminated.

Robot-assisted handling solutions: compact, flexible and quick
Space is an expensive commodity, especially in cleanrooms. The manufacture and maintenance of these plants where an extremely high level of hygiene is required are extremely costly. Compact components are all the more important as ultimately, the machine needs to be space-saving. Mitsubishi Electric components such as SCARA and articulated arm robots, controllers and servo drives are characterised by their particularly space-saving design and are suitable for flexible applications even when space is restricted. Easy handling enables fast integration, commissioning and adjustment.

One example of a highly compact handling solution came from Robotronic AG. Their required a secondary packaging solution for supplying and packing filled vials of various sizes. The solution needed to be integrated in an existing system with limited available space. The modular design principle of the modular robot technology (MRT) produced by Robotronic provides excellent design flexibility. As a result, the basic module for the MRT cell has a footprint of just 1.0 x 1.30 metres and is approximately 2.20 metres high, so it also meets the minimal space requirements. The solution for the cleanroom class in accordance with GMP standard level D consists of two MRT cells, each with a compact robot from Mitsubishi Electric and a conveyor line with eight positioning screws, driven by Mitsubishi Electric servo motors. The robots place the vials in the blister packs at a processing speed of 300 units per minute.

Hygiene in cleanroom systems
The increasing use of automation technologies, especially robots, has led to an increase in the demand for systems which meet high cleanroom requirements. It is also just as important to be able to clean a plant before a production changeover without any major costs being incurred. That means that it must be possible to clean the components in place (i.e. be CIP-compatible) using aggressive chemicals like H2O2. For that reason, Mitsubishi Electric also offers its customers multi-resistant versions of its new generation of MELFA robots which have been approved for regular CIP cleaning using H2O2. MELFA robots can even meet cleanroom class requirements; ISO 3, are dust proof, and have IP67 environmental protection.

@MitsubishiFAEU #PAuto

Treating wastewater as a resource.

A number of British landfill operators are turning wastewater into a resource by utilising OTT monitoring and control systems to manage the irrigation of Willow crops (for renewable energy generation) with pre-treated effluent.

Leachate from landfill sites represents a significant potential environmental liability, extending long into the future after a landfill site has closed. Conventional treatment and disposal options involve biological treatment and consented discharge to either the wastewater treatment network or to the environment. Alternatively, effluent may be collected by tanker for treatment and disposal off-site. However, to improve sustainability and broaden the treatment options, work initiated in the 1990s developed an approach that sought to use effluent as a source of nutrients and water for a Short Rotation Coppice (SRC) crop planted upon the restored landfill.

Willows fed on wastewater!

Willows fed on wastewater!

Following the success of early trials, the Environment Agency published a Regulatory Position Statement in 2008, which said: ‘SRC as part of a landfill leachate treatment process… is a technique (that) can be an environmentally acceptable option if managed appropriately.’

Early systems were operated and managed manually but with the addition of OTT sensors, telemetry and control systems, the process was automated to optimise irrigation and maximise both the disposal of effluent and biomass yield.

Willow SRC has become increasingly popular in environmental restoration work, providing a cost-effective material for stabilisation and reclamation of disturbed landscapes, bioremediation and biomass production.

SRC involves the planting of high yielding varieties of willow at a high density, typically 15,000 plants per hectare. The crop can be expected to last for around 30 years, with harvesting taking place every 3-5 years, and yields varying from 8 to 18 tonnes of dry woodchip per hectare per year. Willow grows quickly and has a particularly high demand for water, so it is ideal for the disposal of large volumes of treated effluent. In addition, the high planting density results in the development of a dense root hair system; effectively creating a biological filter for the treatment of organic compounds and the absorption of nutrients and some heavy metals. Soil fauna help to break down the effluents applied to the crop and soil particles control the availability of nutrients to the willow.

Monitoring and control
In early schemes, irrigation was managed manually on a timed basis with irrigation quantities based on external estimates of evapotranspiration. However, increased levels of monitoring and control are now possible. OTT’s Matthew Ellison explains: “The key objective is to supply the crop with an optimised amount of water, whilst minimising the requirement for staff on site. Too much irrigation would cause run-off and too little would under-utilise the treated effluent and result in poor growth conditions which would affect yield and potentially threaten the crop.

Soil moisture sensors

Soil moisture sensors

“An on-site weather station feeds local weather data to the system which uses crop data to predict evapotranspiration that is used to determine irrigation rates. Soil moisture sensors then check that soil moisture status is correct. Other sensors monitor the performance of the system; checking irrigation feed reservoir level, in-pipe pressure and there are sensors to check flow rates from the drip-feed irrigation. This communication capability is made possible with OTT’s Adcon Telemetry radio network.

“Our latest monitoring and control equipment automates the management of the system for unattended operation and staff are only required by exception. This means that the system is able to operate autonomously, delivering regular data reports, and staff are notified by email or text if alarm conditions occur.”

Emphasising the advantages of controlling the entire network, Matthew adds: “This system facilitates the ability to control and synchronise the main pump, and to open and close the valves at each irrigation zone.”

The latest OTT monitoring and control systems include:

  1. Soil moisture sensors
  2. Irrigation tank level sensors
  3. Irrigation function check sensors
  4. Pipe valves and pressure sensors
  5. Automatic weather station (to calculate local evapotranspiration)
  6. Radio telemetry
  7. ADCON Gateway and PC running addVANTAGE software
  8. Internet connectivity for remote log in

Looking back over a number of SRC projects, Stephen Farrow one of the instigators of this approach in the UK, and now an Independent Consultant says: “When viewed practically, environmentally and commercially, experience has demonstrated the viability of the overall approach.

“It is also clear that process optimisation with relatively low cost investment in OTT’s monitoring and control equipment has significantly added to the support functionality in terms of both operation and regulatory management.’’

OTT’s Matthew Ellison agrees, adding: “SRC clearly offers a sustainable option for effluent treatment, with highly positive effects on carbon footprint and biodiversity.

“In addition to the environmental benefits, process automation has significantly reduced labour requirements and helped to demonstrate compliance with the site-specific requirements of the Environment Agency.”

Society goes to the polls.


Irish candidate goes forward for most senior role in Automation Society

The polls were opened recently for the election of leadership positions for 2017 in the International Society of Automation (ISA). The ballot is for election of new leaders by direct vote of eligible ISA members.

This year for the first time a candidate from the Ireland Section has been nominated for the position of President-elect Secretary. This position is a commitment for three years, the first year as Secretary of the Society, the second year as World-wide President and the third as Past President.

Those nominated for this (and indeed all officer positions in the Societed) are subjected to a rigorous pre-nomination process before their name is placed on the ballot paper. Nomination for an elected Society leadership position is an honour accorded to only a small percentage of the ISA membership.

Brian_J_CurtisBrian J. Curtis (G E Healthcare) Cobh, County Cork, Ireland (right), is one of the candidates this year. He has an impressive leadership background both in the automation industry and in other sectors industrial, commercial and recreational. He has 35 years Pharmaceutical Control Systems experience.

Speaking recently he told us that he has been a member of the ISA for over twenty years and has served in most offices in the very active local section. “I joined my local section to access ISA technical meetings, technical papers, standards and networking opportunities.” However he was also willing to participate more actively in the running of the Section and later in the greater Society, in Europe and Globally.

Brian served in many portfolios within the Ireland Section down through the years including a term as section president (1999-2000). He became Vice President District 12 of the Society (Europe, Africa & Middle East) in 2013.  He also served on the ISA Executive Board 2013 to date, and also on the important ISA Finance Committee. The various society offices involved visiting sections in Europe and the Middle East as well as attendance at various Society governance and  leadership meetings.  His service through the years has been recognised by the Society, as a recipient of the Distinguished Society Services Award, as well as recognition at Section and District levels. He says “My current challenge is working with ISA on our five strategic goals!”

electVoting in the Leadership Elections is relatively easy. Go to the ISA Home Page and look for the button “Vote Now” and follow the instructions.
Only eligible members may vote. You’ll need your ISA ID information of course.
The Ballot lists the candidates with a link to their Biographical details. The voting is simply a matter of ticking the candidate of your choice.

He shared his vision for the Society: “That ISA Sections and Divisions all work together so that membership and industry feel the benefits, both locally and globally, ensuring “ONE ISA” will prosper into the future.”

“I believe we must nurture the volunteer in the society and encourage sections, divisions and standards to work together across geographic and technical boundaries so as to harness and build upon the strength and integrity of ISA in meeting the automation challenges of the future.”

He is particularly in supporting the ISA’s pioneering work in the emerging area of cybersecurity. Industry and production methods are evolving at a fast pace and it is important to identify emerging trends and seize these as opportunities for our member’s and for automation.

He wants to strengthen the Society by encouraging co-operation and communications between sections, divisions, standards and all areas of ISA around the world. He is not afraid to support the tough strategic decisions that will allow ISA to continue to be the leader in the automation industry. It is important also to promote the lifelong opportunities that automation presents as a career for school and college graduates.

There are two other candidates for this position. They are Eric C. Cosman (OIT Concepts, LLC) Midland, Michigan, USA. He was one of the speakers at the groundbreaking Food and Pharmaceutical Symposium in Cork earlier this year. The other candidate is Glynn M. Mitchell (US Nitrogen) Greeneville, Tennessee, USA.

Although most of the Presidents of ISA since its foundation have hailed from the US there have been a handful of Presidents from other regions of the World.

#ISAuto #PAuto

Reduce data centre asset liabilities.

How you implement RFID monitoring is critical to the performance of the system.

Harting_Data_Centre_AppWith regular headlines about the latest cybercrime attack stealing important or commercially sensitive data, the physical security of IT equipment is often overlooked. One area in particular is the almost casual theft of small pieces of equipment from the racks. For example, the latest helium filled 10TB hard drive represent a €700  (£600stg) investment and with up to 22 drives used in a 4U storage array, loss through theft can be substantial.

The constant monitoring of what equipment is located inside the data centre has additional benefits not only in terms of security but also in managing cooling air-flow requirements and power consumption, which support growing need to demonstrate compliance with Green IT initiatives.

In response, data centres have been increasingly looking for cost efficient solutions for key asset management. Data Centre Infrastructure Management (DCIM)* is an emerging holistic management approach that combines traditional data centre equipment and facilities with monitoring software for centralized control. DCIM includes physical and asset level components and by combining both information technology and facilities management it raises the effectiveness of a data centre.

RFID has been seen by many as a key element to providing real-time monitoring of component location within the data centre. By installing passive RFID tags on every removable component of the rack data centre systems integrators and site operations managers can easily use them not only to record locations but more information about the device than they could before with standard asset tags.

But how you implement RFID monitoring is critical to the performance of the system.

Portable hand-held RFID reader systems have a very small UHF read range and only offer a slightly better performance than relying on paper records or barcodes because it requires employees to walk down aisles and identify the piece of equipment and its location. This is a very time-consuming task and as such is not undertaken very often. It also relies on the competence and integrity of the operator carrying out the check.


Fig 1

Up until now it has been unrealistic from a physical location point of view to directly integrate even the most compact passive RFID UHF patch antennas into existing data centre server rack arrays.

Typically, 4 antennas would have to be separately mounted either side of the front of each server rack, in both the upper and lower areas and carefully positioned to ensure there are no gaps in the RF field coverage. Correspondingly, with such an arrangement it would also be necessary to utilise multiple readers, resulting in excessive installed cost

Harting now have the ideal solution to remove this higher cost multiple patch antenna and reader arrangement with its innovative Ha-VIS RFID LOCFIELD® coaxial cable waveguide antenna.

They can be directly integrated, with insulating spacers, onto the rear side of the front access door of each server rack. Only one of these Ha-VIS RFID LOCFIELD® antennas needs to be fitted for a fully installed 45U sever rack. By fitting in an extended S-shape design (See Fig. 1) you can achieve the best possible RF field coverage of the complete rack. In conjunction with a single reader which has the required power to match the correct read distances, it can register passive RFID tags that provide specific item identification within a rack and additional sensor functionalities e.g. detecting empty or occupied slots, thus minimizing the complete data centre system installation cost.

The Ha-VIS RFID LOCFIELD® is a traveling wave RFID antenna consisting of a coax cable that—when plugged into the antenna port of a Harting UHF EPC Class1 Gen 2 reader—conveys the reader’s RF signal along the cable’s copper core and to the antenna’s far end, where a coupling element draws the RF wave out and onto the cable’s exterior. When that signal reaches the reader, a metal protecting shield prevents the interrogator from receiving its own signal and interfering with its performance. N.B. The Ha-VIS LOCFIELD ® antenna should not be mounted directly onto a metal surface but raised-off slightly with insulating spacers.


Fig 2 – Harting HA-VIS RFID LOCFIELD® antenna

By its functional nature the Ha-VIS RFID LOCFIELD® antenna facilitates real-time monitoring of movements in and out to the rack enclosure and is available in different lengths up to 10 metres and is 5 millimeters in diameter. If used with a high-powered reader, such as Harting’s Ha-VIS RF-R500 long range reader transmitting a signal of 4 watts (36dBm), it can read passive EPC Class 1 slot Gen 2 transponders located up to 2.5 metres away radially over its entire length.

Put simply Harting’s Ha-VIS RFID LOCFIELD® antennas allow you to identify what is in a data centre rack, its population status and where a specific item is located.

* DCIM was originally defined in the US and describes a methodology of IT and facilities management.
@Harting #PAuto

Brexit woes continue.

This is a short piece from Nick Denbow, in the July Issue of Industrial Automation Insider*  on the aftermath of the Brexit referendum. See our earlier piece “Nobody knows!” (30/6/2016)

The first thing that Great Britain’s new government, under Prime Minister Theresa May and Foreign Secretary Boris Johnson, did was to quash talk of a new referendum that might end Brexit before it actually gets started. The government says it plans to go ahead with the exit of Great Britain from the European Union, despite angry words from Scotland and Northern Ireland, both of which client states voted emphatically to stay in the EU.

zollschildThis impacts manufacturing and automation system companies in quite a few different ways. The membership of Great Britain and Ireland in the EU made it possible to conduct business across country barriers with so much ease that the borders were essentially invisible. Personnel could be sent wherever needed, not where they were citizens. Inventory could be stored anywhere in the EU for shipment anywhere in the EU and things like FAT tests and FEED projects could be done anywhere without regard for borders.

“The connection of just about anything via the Internet is expected to grow rapidly through 2016 and well into the future, significantly boosting opportunities for tech specialists, particularly cybersecurity professionals. Complicating this is the recent investment by the EU of US $500 million to fund research into cybersecurity, and its call for industry to invest at least three times that amount to protect the EU economy from cyberattacks. Under the plan, the European Commission (EC), the EU’s executive body, has launched a public-private partnership under the European Cyber Security Organization, which calls for EU member states and cybersecurity bodies, including market players, research centers, and academia, to strengthen their cooperation and pool their knowledge to increase Europe’s cyber resilience. It’s not clear at this point where, or if, the UK would fit into this program.” –Ron Schnieiderman on IEEE Careers site.

This will no longer be true, as Brexit takes hold, and companies are now having to do significant amounts of strategic planning based on this very large Great-Britain-sized hole in the EU. Further, other countries are making noises like they might want to break up the EU entirely, which is a different bucket of fish entirely. European automation companies have prospered because of the borderless and customs-less conditions under which they have worked in the EU.

It will be interesting to see how this unfolds, especially with Scotland making independence noises again, less than two years after a failed independence plebiscite.

• The Insider’s Health Watch column also reports on some Brexit related influences!
• Coincidentally the ever-interesting BMON daily had a popular piece on the possible effects of the Brexit decision on the internet – specifically the use of cookies –  The Future for EU and UK Laws on Cookies after ‘Brexit’ (3/7/2016)

*The Automation INSIDER is an independent monthly e-mail newsletter and editorial report on the continuing evolution, development and convergence of industrial automation, instrumentation and process control technologies worldwide for automation and process control system users, designers, installers and suppliers. It is compiled by Walt Boyes.