Process Control Systems

Process control systems (PCS) are a vital element in maintaining efficiency on a manufacturing production line, by testing the characteristics of the products to identify any abnormalities which can then be quickly attended to. PCS devices are also able to extract any data about these anomalies to ensure procedures are adapted and maintained, and to allow for faster troubleshooting if the issue occurs again.

PCS is a broad term that refers to pieces of equipment which carry out the above function, but there are great variations in types of PCS. At a fundamental level, the PCS must include a sensor, or primary transducer, which receives an input of data from a measurement taken on the production line, a controller which processes this input in line with desired setpoints (SPs), and a receiver which processes this into an exportable data output. This data is then transmitted to the company’s enterprise resource planning (ERP) computer application through a manufacturing execution system (MES), before control valves in the production line are altered, following an abnormal reading.

Smaller and more basic PCS devices, therefore, only require a combination of modular panel-mounted controllers to fulfil their function. Larger systems, however, are more complex, and are most often administered by one of three types of PCS: supervisory control and data acquisition (SCADA), distributed control systems (DCS), or programmable logic controllers (PLC).

What does the PCS measure?

In order to regulate the equipment on a production line, PCS devices measure process variables, of which there is a huge range, including pressure, flow rate, velocity, temperature, density, acidity, speed, stress, and weight. By measuring these variables, the PCS can identify irregularity in the products, which imply a necessary alteration in the production line equipment. By weighing and testing a container, for example, a sensor might detect whether it has been filled with its contents correctly and in the right quantity, when this data is compared with the SPs. In simple sensors, a pressure reading is given on an attached dial, to be manually recorded. In PCS devices, however, this reading is electronically transmitted to the MES application.

Similar methods are used across sensors with different measurement focuses. The most common of these is the measurement of the extent to which an element of the sensor is affected by an item. For example, piston sensors detect the pressure of an item by the force it pushes onto a spring, the movement of the spring then being measured to gauge the pressure. Mechanical gauge force sensors, much like the piston pressure sensors, use a spring for the item’s force to be tested again, the movement of the spring being proportional to the amount of force applied. Inferential flow meters also measure flow based on its effect on a piston or rotor arm, the speed of movement of which indicates the flow of the liquid or gas. With bimetallic temperature sensors too, the heating of metal strips causes them to bend, moving a pointer on a dial to reveal the measurement.

Other sensors use liquid as a medium through which to take a measurement. Liquid expansion temperature sensors work in a similar way to thermometers, measuring the expansion or evaporation of a liquid by the pressure it exerts on the sensor. Hydraulic load cell force sensors test the pressure of a liquid in response to a force and can also be used well for comparative measurements. Differential flow meter sensors also use comparative readings in their measures of flow as differential pressure.

 

 

 

 

Is DualTEC SafeContractor Accredited?

Is DualTEC SafeContractor Accredited. Yes, we are. But what does this mean for you, the customer?

Health and safety is a priority that can’t be ignored, and DualTEC Services Limited is a business with a culture of taking health and safety seriously. Our SafeContractor Accredited status is your guarantee that our paperwork and processes comply with current health and safety legislation and standards. We are committed to sustainable and ethical practices that ensure the health and safety of our employees and our customers in the best way possible.

What Is Alcumus SafeContractor?

Alcumus SafeContractor is a third party accreditation scheme that assesses the health and safety arrangements, policies and qualifications of contractors. Many major clients recognise the scheme and accept the SafeContractor certificate as confirmation of competency in health and safety practice.

Under the SafeContractor scheme, businesses undergo a vetting process which examines health and safety procedures and their track record for safe practice. Those companies meeting the high standard are included on a database, which is accessible to registered users only via a website.

Client organisations who sign up to the scheme can access the database, enabling them to vet potential contractors before they even set foot on site. These clients agree that, as users of the scheme, they will engage only those who have received accreditation.

Over 470 major, nationwide businesses, from several key sectors, have signed up to use the scheme when selecting contractors for services such as building, cleaning, maintenance,refurbishment or electrical and mechanical work.

DualTEC Services Limited SafeContractor Certificate 2021-2022

Another year of SafeContractor Accreditation!

We are Specialist Electrical Engineers and Control Panel Builders based in Keighley, West Yorkshire, UK. We provide full UK coverage and tailor our services to our customers’ specific requirements. Our SafeContractor certificate means you can rest assured that we meet the necessary requirements around health and safety, equal opportunities, diversity and environmental management practices.

If you would like to discuss your requirements or request more information please get in touch –

T: 01535 609314
E: info@dualtec.co.uk

 

Please don’t excuse the mess: keeping your electrical control panel clean

Poor and irregular maintenance of an electrical control panel can, unsurprisingly, lead to huge pay outs for repairs and replacements, as the control panel overheats and components malfunction. In order to prevent this costly consequence, we have a few tips and tricks for kick-starting and maintaining a clean electrical control panel.

Dust and Debris

Dust is a catch all term for a range of different substances, some of which are often conductive materials. A build-up of unmanaged conductive material can affect currents, causing short circuits and component collisions. Even a build-up of non-conductive dust can lead to overheating, which causes serious problems for electrical control panels. Regularly scheduled maintenance will help to keep the panel clear of dust and debris.

TIP: A vacuum will clean more efficiently inside the enclosure than compressed air, which might work to push the dust deeper inside the panel, and into unreachable corners.

In regular checks on your control panels, be sure to check the plastic casings and components within your panels, which can degrade and create a build-up of carbon. This is most likely with contact components that arc when opening and closing. Additionally, the older the equipment, the more likely this is to happen.

TIP: When cleaning your panel of carbon and other tough dirt, use specific cleaning products designated for their safe removal.

The Filter is Your Helping Hand

Filters are used precisely for the purpose of preventing dust particles from penetrating the control panel. If your panel came with filters, make sure to follow the guidelines for replacement frequency. If the dirt in a filter reaches above 60-70%, the air flow inside the panel will be compromised, risking overheating and damage to components.

Thinking in preventative terms, there are a number of ways you can ensure your filter has the best chance of protecting your control panel from debris, and therefore doing most of the cleaning work for you. Control panels in which filters are positioned outside the enclosure both keep the dust as far away from your components as possible, and are easily accessible for regular replacement.

Buying affordable filters will also encourage you to replace them more frequently, preventing more costly damage to your panel. Some brands also manufacture washable filters, which again contribute to keeping filter costs low.

TIP: Keep a few filters in stock, so there is no option for procrastinating when your filter needs changing.

The Importance of  Control Panel Design

While regular maintenance and cleaning are important for any control panel, custom control panel builders can limit the necessary frequency of this upkeep. Specialist engineers can support the building process to ensure the design of your control panel supports efficient and cost-effective operation.

The highly specialist team at DualTEC can provide this support through the process of your control panel design. Call today on 01535 609314 to speak to our support staff, or visit our contact page  to get in touch

A Guide to Best Practises for Electrical Control Panels

Industrial mechanisation and equipment now universally rely on electrical control panels for operating and automating their essential processes. The essential position of electrical control panels in modern industry and manufacturing thus requires high-level and faultless engineering of these products. But in order to maintain their safe and reliable operation, prevent component collisions and incurring large maintenance costs, the following practices must be considered.

Logical Organisation

The importance of organisation in the production of electrical control panels should not be underestimated. Components should be logically positioned in terms of function and electrical requirements, for ease of identification. Following this recommendation, DualTEC have a clear outline for panel organisation. They position circuit protection components proximately to one another in one area of the panel, and near to the necessary devices. Another section of the panel holds group drives, and the PLC is positioned at the top.

Clearly labelling wires and components also ensures more clarity in the organisation of your electrical control panel. Using a consistent syntax or abbreviation type aids this process. We advise using an abbreviated prefix in labelling, such as CB for circuit breaker, and PS for power supply. These labels should be placed visibly on the front of the device and at both ends of each wire.

Our use of wireway to create banks to hold components also ensures short, efficient wire runs, and allows for a neat composition of wires which could otherwise interfere with components. Placing an emergency-stop (e-stop) button in the most visible location on the panel door, and separate from other buttons, ensures the safest control panel operation. This way, it can be easily seen and accessed in an emergency, but the potential for accidental engagement is limited.

Appropriate Enclosures

Choosing the correct size enclosure to hold your panel components is also more than just a space-saving procedure. With components slotted closely together, collisions with door-mounted devices are prevented. DualTEC like to pre-empt any problems, with panel layouts modelled clearly to prevent, in advance, any risk of component collisions.

Not only the size, but the material of enclosure is vital to supporting the safe operation of your control panel. Polycarbonate plastic, mild steel, stainless steel, and aluminium are among the most common materials used, and each holds different benefits and corresponding NEMA ratings.

Polycarbonate plastic is inexpensive and holds high impact resistance, suitable for indoor and outdoor use. The NEMA ratings for polycarbonate plastic enclosures range between 1, 2, 3, 4X, 12 and 13.

Mild steel is commonly used in electrical enclosures, and successfully protects control panels in wet, non-corrosive spaces. These enclosures are offered in NEMA ratings 1, 2, 3, 4, 6, 12 and 13.

Stainless steel is equally versatile in wet environments, and additionally is fire resistant. Yet alongside these benefits comes a greater cost with this material, and a heavier weight. Stainless steel enclosures NEMA ratings range across 3, 3R, 4, 4X, 12, and 13

Aluminium is a stable and reliable material, fit to withstand high temperatures and resistance to corrosion. Its natural EMI/RFI shielding also prevents interference, and its NEMA ratings range between 3, 3R, 4, 4X, 12 and 13.

Temperature Control

Improperly engineered electrical control panels are prone to overheating, and so heat dispersal must be seriously considered in their construction. Among the causes of overheating are inappropriate enclosure ventilation; exposure to sunlight and natural elements outside without correct protection; locations close to hot machines, ovens and furnaces; and poor maintenance leading to a build-up of dust inside the panel.

DualTEC endeavours to ensure that temperature control elements are incorporated into electrical control panels, altered depending on individual specifications. These components include side-mounted air conditioners, vents, fans and air to air heat exchangers, to ensure a constant temperature is maintained inside the panel. Additionally, advice can be given on the location and enclosure material for your control panel, and regularly scheduled maintenance will keep the panel clear of dust and debris.

DualTEC

Located in Keighley, West Yorkshire, DualTEC pays great attention to these practices in the engineering and construction of their control panels. The qualified team at DualTEC can comfortably and efficiently carry out your automation project.

In addition to industrial electrical control panels, DualTEC provides a great range of control system services including PLC and HMI programming, machine automation systems, energy management and refrigeration syste

Why Outsource Your Control Panel?

Outsourcing has, from its beginnings, been considered a valuable practice for ensuring cost-effectivity in business projects. Yet this progressive approach to project management is profitable beyond the reduction of on-the-ground operational costs. Outsourcing can relieve you of the time-consuming and costly activities of project organisation and the provision of expert customer support, whilst also providing you access to leading specialists (like our team of control panel specialists here at DualTEC), and state-of-the-art technology at a fraction of the price it would cost to establish these infrastructures in-house. To make your project hassle-free and cost-effective, consider outsourcing the engineering and production of your control panels, for these five key reasons.

Keeping basic control panel costs low

A commitment to reducing the costs attached to your project inevitably remains a key incentive for the outsourcing. As opposed to the production of control panels in-house, outsourcing removes the great expenses and length of time associated with self-administering operational staff and resources. The process of design and engineering is streamlined to ensure that you only pay for the costs associated with the product itself, with the outsourcing company taking financial responsibility for the complex network of subsidiary expenses.

Access to the most advanced technology

The ever-changing world of control panel technology is hard to keep up with when these projects are run in-house. The up-front costs, expensive licensing and user fees, and maintenance of these technologies can run up very high bills, causing great expense. Outsourcing instead allows you access to the newest technology on-hand, with additional fees covered by the outsourcing company. This will keep the process of administering your control panels straightforward and low-cost, while you can rest assured that you are operating your service with the most advanced technology.

Your pick of leading experts

In addition to providing access to the most sophisticated equipment, outsourcing also connects you with a great array of specialist assistance. The freedom to select from this smorgasbord of experts ensures that your control panel is engineered and designed by the best, at a fraction of the price of employing just one of these specialists full-time.

Projects managed with clarity and precision

Alongside the provision of top-quality technology, designed and engineered by respected experts, DualTEC can provide clear and transparent organisational structure for the project. Where in-house projects are susceptible to running over deadlines, the delays from which waste vital money and time, projects led by outsourced companies are laid out with clear logistical frameworks which reduce time to market. DualTEC work directly with contract manufacturers to attain clear timelines and pricing, eliminating unpredictability whilst reducing the workload for your in-house team.

Dedicated support for you and your customers

Outsourcing also provides exclusive and cost-effective benefits beyond just the design and production of your control panel. DualTEC have established teams of dedicated support staff are on hand to consistently monitor your equipment and provide a streamlined service for your customers in the diagnosis and repair of any technical issues. The staff and financial resources underpinning DualTEC’s customer support services ensure that you are providing the best for your customers, and avoiding delays in maintenance of your technology, keeping costs low by maximising productivity.

Outsource with DualTEC

Based in Keighley, West Yorkshire, our highly experienced specialist team can offer competitive prices for control panel outsourcing, to reduce the financial and logistical strains on your project. For further information about our outsourcing provisions, don’t hesitate to call on: 01535 609314, or contact the team at: info@dualtec.co.uk.

The benefits of automation to industry

Around 20 years ago, an article about automation was accompanied by a cartoon. The cartoon was split into two halves; on one side was a factory worker saying to his colleague ‘no matter how far automation goes, they’ll always need people like us to push the buttons’, unaware that on the other side was a picture of the factory boss interviewing a robot in a suit.

Change can be overwhelming, especially in circumstances where workers see a loss of control over jobs, and the percieved need for human interaction gives way to automation, but we should remember that there are huge benefits to automation in industry.

Lower operating costs from automation

Depending on the task at hand, automation can perform the work of many people. As well as these reduced costs on labour, there are lower costs of heating an automated environment. Because of the streamlined processes that automation brings about, part accuracy is increased which results in less material waste.

An improvement in worker safety

There are many horror stories of jobs lost when plants were automated, which has been happening for decades now, and of course, automation can lead to consolidation of operations, meaning plant closures and their brutal impacts to local economies.

Whilst it might feel like a small compensation to the remaining workers, there has been a huge increase in worker safety due to automation.

The elimination or improvement of dangerous work such as lifting and moving heavy or unwieldy objects has been a key contributor to a reduction in back injuries. Automated pick-and-place systems, automated palletisers and vacuum hoist systems are all in place in many factories. Repetitive lifting tasks, andlifting more than 20 kg have become progressively rarer throughout industry.

Reduction in factory lead times

Automation can keep your process in-house, improve process control and significantly reduce lead times compared to outsourcing or going overseas.

Increased production throughput coupled with consistency

Automated machines and computers work at a constant and continuous pace, and they allow a factory to work 7 days a week, 52 weeks a year. There’s less variability in the product produced under these conditions than with products produced manually, which leads to greater product control and quality. New products can be quickly introduced into the production process quickly, as new product programming can be done off-line without disrupting existing processes.

Increased system versatility

Automated systems can be easily re-tooled and repositioned for new production lines. The same equipment may be used on multiple production lines, as different automated tasks can be programmed into the same equipment without it having to be completely rebuilt.

Can automation create more jobs, not fewer?

During the industrial revolution in the UK, 98 percent of manual labour involved in weaving cloth was mechanised, and there was considerable worker unrest. But despite worker concerns, the number of textile workers exploded, as costs plummeted and demand grew. Jobs changed from hand-weaving to operating weaving machinery. The same principles stand true today. Automation generally eliminates dull, tedious and repetitive tasks, but it can bring about increased demand for goods as they get cheaper; and as the character in the cartoon said: ‘They’ll always need people like us to push the buttons’.

Get in touch with DualTEC

From our premises in Keighley, West Yorkshire – we design, build and distribute cutting edge control panels to aid factory automation for companies across the UK. If you have any questions whatsoever, regarding our automotive control panel services or indeed any of our other services – please don’t hesitate to get in touch with one of the team at: info@dualtec.co.uk or call on: 01535 609314

Programmable Logic Controllers and Industry 4.0

The Programmable Logic Controller (or PLC for short) can automate specific processes, machine function or even whole production lines. As industrial devices, they can be used as part of a network with other PLCs, or simply as standalone units.

In recent years, PLCs have played their part in the digitisation of manufacturing, alongside other important elements which enable machine connectivity and process automation. The digitisation of manufacturing has evolved so quickly that the term ‘Industry 4.0’ has been coined.

Industry 4.0 is the term used to represent a wide range of new technologies which promise to accelerate the pace of change in manufacturing. A combination of sensors which are always connected, artificial intelligence, machine learning and blockchain storage will allow sense to be made of masses of information. This represents nothing short of a new industrial revolution.

With 5G internet connection, we can also expect to see a massive increase in Internet of Things (IoT) connectivity, whereby sensors speak to each other in real time, with no lag, sending data directly and instantly to the cloud in order for it to be made sense of and acted upon. This ability to send live production data to the cloud will pave the way for real-time reporting.

In this new era of Industry 4.0, programmable logic controllers are likely to play a noteworthy role as the main control, input centre and HMI for workers. PLCs will continue with processing real-time manufacturing processes, but with the addition of Industrial IoT, the information relayed via input sensors will enable PLCs to collect data and transmit it to machine learning programmes.

This data will be able to be processed by artificial intelligence algorithms and be crunched to reveal anomalies and to autocorrect any errors in real-time.

For many, this is all in the future however. The reality for a lot of manufacturers in the UK at the moment is that there’s quite a long road to travel down before the benefits of Industry 4.0 are available. Budgets aren’t there in many smaller manufacturing businesses to invest in the latest technology infrastructures and software, and such investments need to be considered carefully.

There are some complex questions to be answered by manufacturers about how, and when they should transform their processes towards Industry 4.0. By starting to look at and understand all of your technology, processes and connectivity, manufacturers can also start to understand weaknesses and look at areas to improve on.

A deeper understanding of every process and customer is important if manufacturers are to understand how Industry 4.0 can play a transformational role in their business. Staff are very important holders of knowledge, and should be involved in every stage of information gathering for new technology-based solutions.

Comprehensive Programmable Logic Controller services from DualTEC

From our base in Keighley, West Yorkshire, our experienced and dedicated team offer programmable logic controller installation and maintenance services across the UK. If you have any questions or are looking to enquire about any of our control panel services get in touch on: 01535 609314 or email us at: info@dualtec.co.uk

The Building Blocks of Proportional Integral Derivative Controllers (PID)

Proportional Integral Derivative Controllers (PID for short) are relatively simple yet irreplaceable components that are commonplace within the control panel industry, and despite PIDs being heavily relied on, they’re definitely not without their flaws.

Whilst the basic function of the PID is relatively simple – or at least when they were first introduced to process control – they work within a more complicated loop system, known as Ladder Logic. Ladder Logic gets confusing quite quickly, which only gets worse with each subsequent fault that occurs within a panel, then further compounded by the essential-but-damaging troubleshooting of said faults.

Proportional-only controllers

When they were first introduced, controllers weren’t known as PIDs as their function was ‘proportional-only’. Meaning they were far simpler than their three-charactered progeny that we’re used to today, however, they quickly became unable to handle errors occurring within the panel. Proportional controllers had a tendency to give-out whenever an error between the process variable and set-point needed remedying. As such, it was evident that the function for integral action within the controller was needed, and the proportional controller was updated to suit.

Putting the I in PID: Integral Action

To overcome the latency period created from dwindling proportional action (PA) between the process variable (A) and the set-point (B), electrical engineers soon figured that they could manually bias the control effort. Or put in simpler terms; they could manually reset the loop between points A and B.

It wasn’t long before the manual piece to this puzzle became automated, which further minimised the inherent delay manifested by manual intervention. It is this automatic reset which became what we now know as integral action (IA) or ‘reset rate’. However, integral action is not without its own flaws.

For example, if the process under control is already slow, then the error will take a while to clear whilst the operator employs aggressive integral action to remove it. The issue with IA is that it continues to grow whilst the error is still present, so if the reset rate is set too high, the error will be overcompensated by the controller. This sends an even larger error back in the opposite direction, producing ‘hunting’ cycles back and forth between points A & B – at least until the error is eliminated.

Integral action is appurtenant to processes whose actuator isn’t large enough to produce the required control effort to solve the error, such as an insufficient burner that can’t provide enough heat, or a valve with an insufficient flow rate. This situation is known as ‘actuator saturation’. As the errors between points A and B begin to climb as a result of aggressive IA, there is a limiting value where the actuator bottlenecks, stalling any option of fixing the error.

This bottleneck jams the actuator at 100%, allowing the errors to build to a huge value and renders the controller unresponsive, this in turn prevents the operator from fixing the error – the remedy to which would usually be to reduce the set-point level (B) to a more attainable range.

This type of malfunction is known as ‘reset windup’, and systems are now designed and built with the ability to shut down the integrator in order to protect the controller.

Proportional, Integral and D?: Derivative Action

Derivative action (DA) reduces the control effort in relation to the error’s rate of change, this way the speed at which the process variable (A) is descending to the set-point level (B) can be controlled and reduced. Meaning A doesn’t drop too quickly to meet point B – reducing the chance of hunting cycles as in Integral Action.

That said, this only works as long as the DA is being applied correctly, if it comes on too aggressively as in IA – it will cause hunting of its own. More often seen in the control of robotic equipment and motorised apparatus as they are quick to respond to the controllers command.

Because DA responds to the error’s rate of change, it can sometimes cause the control effort to spike if an error occurs or changes suddenly. Under these circumstances, the derivative action would immediately kick into action, long before the proportional or integral elements of the PID will. Each element of a PID controller has its place, which is why two-term PI controllers or just straight-up proportional controllers are not often in use.

The only situation where this level of predictive control is detrimental, is in a situation where the end result of a spike from derivative action could be dangerous. For example, the control of heat in an industrial blast furnace. To mitigate this risk, modern PIDs have been developed to include:

• reset windup protection
• a derivative action calculator – to ensure accurate operation
• noise filtering – to reduce spikes and surges
• loop tuning – allowing appropriate value selection for proportional, integral and derivative action, narrowing the gap in response time to changes in the process variable

Need more info? Contact the DualTEC team today

If you would like to discuss the application of PIDs into the design of your process control setup get in touch with our team of electrical engineers for more info. With over fifteen years experience as a company, and a collective knowledge surpassing the majority of control panel builders today – we’re well placed to help. Just call 01535 609314 or email info@dualtec.co.uk.

Circuit Protection for Power Distribution

When designing control systems, power distribution is an important factor for consideration. The features of distribution included in a control panel setup ultimately determine the operational efficiency, productivity and safety of the intended working environment. It goes without saying that the power distribution designs need to be thorough, so that the entire panel is protected from overloads and faults, as well as protecting the user.

The issue that electrical engineers face, is that there isn’t a definite set of criteria to follow when designing the power distribution elements within a control panel. What we do have, are the British and European standards and their corresponding codes. The rest really boils down to experience and intuition, the latter of which is earned through years of practice.

DualTEC’s electrical engineers have a collective knowledge that far surpasses our impressive 15 years in business, and it is that experience which enables us to design and build products that make circuit protection for power distribution an inherent part of all our control panels.

Considerations for power distribution in control panel design

There are two overarching goals when designing power distribution into a panel build. There needs to be an ability to localise and isolate the fault in question, this then prevents or at least minimises any needless loss of power.

Whether the control system is intended to govern automated factory equipment or route power across the national grid, short circuits and overloads are to be expected during a building’s operational life. To avoid damage to either the internal parts of the control panel, machinery within the building or both – localising and isolating the fault is essential.

So what protection should be included in the control panel design?

The two most common forms of circuit protection for power distribution in control panels are overcurrent protection and ground-fault protection.

A ground-fault is where a break in the circuit ‘grounds-out’ or connects with the grounding point, usually the equipment frame. This is normally as a result of faulty or broken insulation, effectively making any conducive element in the panel ‘live’ – including the user. As the name would suggest, overcurrent is where more electricity than intended is passed through a conductor, generating excess heat which in turn increases the risk of component damage or even fire.

Protection against overcurrent comes in the form of specific devices. Circuit breakers, relays and fuses are the three most basic and fundamental OCPDs (overcurrent protection devices) that should be incorporated into any control system. These components are intended to break, isolate or blow whenever overcurrent is present.

Fuses are the simplest form of protection, consisting of a single strand of wire with an amperage rating higher than the recommended load for the circuit. Overcurrent increases the current by at least four times the recommended load, so under these conditions the fuse blows and breaks the circuit. Circuit breakers work on a similar basis, with the key difference being that the ‘break’ is reversible, unlike fuses. Relays act as a switching device, which gives a signal to the circuit breaker as soon as a fault in power distribution is logged.

Ground-faults are by their nature harder to detect, as the current tends to drop rather than surge, like in overcurrent protection. They are particularly difficult to locate in arcing ground faults, where the break in insulation creates an arc of electricity from the circuit to the control panel frame or body.

Generally speaking, the aim with ground-fault protection is to firstly protect the user, and then to protect the equipment within the control panel or the building. Ground-fault circuit interrupters (GFCIs) should be implemented into the design and build, acting as a circuit breaker during line-to-ground faults. This provides automatic protection against electric shock from accidental grounding, both for the user and sensitive internal components.

Speak with the DualTEC team for more information on integrating circuit protection into your control panel

This article aimed to provide a guide of which essential elements of circuit protection should be integrated into modern control panels. Whilst we have simplified the process in this overview, DualTEC’s team of electrical engineers has a wealth of knowledge and experience that can be applied to all manner of projects and industries, however simple or complicated. If you would like more information on our control panel design and building service, don’t hesitate to get in touch with us on 01535 609314 or email info@dualtec.co.uk.

SCADA Systems and Process Control

SCADA, or Supervisory Control and Data Acquisition, is one of the most widely used acronyms in the control panel industry. Having an intricate knowledge of what it is and how it actually works, is integral to the design and manufacture of process control systems. Below, we discuss what makes up a SCADA system, its purpose and how the information they collect is utilised.

What is a SCADA system?

First and foremost, SCADA is a software package, designed to control and monitor equipment in industrial settings. The software element to the system is responsible for gathering and handling data, locating trends and providing diagnostic information on the operation at hand.

Utilised in a wide variety of settings, SCADA systems control most manufacturing, fabrication and production processes, as well as being used in infrastructure for the power, water and the oil & gas industries. The central control system is part software, part hardware – all connected via input/output supply, controller network interfaces and communication equipment.

Simple SCADA system diagram by DualTEC

Together, hardware and software work simultaneously to gather data on whichever process has been assigned for monitoring. Control is then governed either by RTUs (Remote Terminal Units) or PLCs (Programmable Logic Controllers), allowing panel operators to set up logs for analysis, adjust alarm parameters and modify set points.

The hardware in SCADA systems is defined by two layers, the client layer and the data service layer. As the name would suggest, the client layer of hardware takes care of the interaction between man and machine, often consisting of some form of HMI (Human Machine Interface). The data service layer is responsible for all of the data processing within the system – connecting field devices via WAN or LAN networks to RTUs, which convert signals from those field sensors into digital format. That data then determines which control signals will be generated and ultimately sent on to the relays.

These various elements are connected by a combination of wireless and wired technologies and may need to run proprietary protocols, if built by the same manufacturer. For example, Profibus and Conitel’s communication protocols are vendor specific (proprietary), whilst Schneider Electric’s Modbus RTU is open source.

How do SCADA systems work then?

The working procedure of a SCADA system is performed through a combination of software and hardware as mentioned above. Sensors, RTUs and controllers are connected via the comms network to handle data in stages, with aim of executing the primary function of control. The following stages should always be considered during control panel design:

  • Acquisition – quality data acquisition and collection is the keystone to accurate means of control within a given system. Where thousands of sensors or nodes are critical for operational function, the ability to monitor the status of those nodes is essential
  • Communication – SCADA systems are often intended to govern processes in multiple geographical locations, so wireless connectivity is the norm. During the R&D phase, secure internet access via a VPN should be factored into designs for security purposes
  • Presentation – HMIs are an integral part of a SCADA system, enabling the user to view data collected from multiple sources in a format that is easily understood and easily actioned

Acting on the data collected, monitoring and controlling the process intended, is generally an automated process. The user defines specific parameters that are enabled when the right data is fed back into the system from the sensors – though critical tasks are sometimes set to require additional input from the user as an added security measure.

Reach out to the DualTEC team for more info

SCADA systems are easily scalable, making them well suited to a wide variety of businesses, whether in one location or several. If you would like to discuss the adaptability and application of SCADA systems into the design of your control panel, DualTEC’s team of electrical engineers are well placed to do so. For any further information, just call 01535 609314 or email info@dualtec.co.uk.