May 2021

44 May 2021 www.drivesncontrols.com B eing efficient isn’t just about having the right tools. It’s about using them correctly. The same goes for the concept of the smart factory. Having a smart factory doesn’t necessarily mean buying in tonnes of high-value, fancy-looking kit, but analysing your existing equipment and asking the question: how can I get the best use out of what I already have and perhaps modify and/or upgrade it to maximise its efficiency? This is the first step that should be taken when starting the journey towards improved productivity and maximised efficiency. When talking to SMEs, it is apparent that to get started on a journey – be it digitalisation, energy efficiency or even increasing profits – the first step is to look back at your business problems, find out what caused them, and build a solution to fix the existing issues. Once that has been done, and any manufacturing bottlenecks have been eliminated, it is much easier to justify any investments or improvements that follow. Using the right equipment for the right application is vital. Nearly all factories have a variety of drives, motors, relays, switches and more, yet are we certain that the correct products are being used for the correct applications? I’m not so sure. Some technologies are marketed as packages and these could be an overkill for your requirements, leading to higher costs or greater energy wastage. For example, there is long-standing discussion about whether soft-starters or variable-speed drives are“better”. It all comes down to the application and considering“why” this form of control is required. The main factor in helping to choose between these two technologies is the speed of the application. If you need to change the speed of a motor continually then a variable-speed drive is usually the best approach. If the application runs at a set speed, then a soft starter will usually be preferable. These fundamental basics should not be overlooked. In both methods as a motor reaches certain operating speeds, the counter electromotive force increases to limit current to steady-state conditions. In other words, both methods demonstrate an improvement in energy efficiency and can extend the life of the motor itself. It all comes down to user intent. Inevitably, the goal of implementing a system is to cut user costs. Individual businesses need to define what is cost- effective to them. It could be the initial cost, trying to keep capital expenditure low, or perhaps minimising running costs and looking at the general overheads, or aiming for long- term year-on-year energy savings. The fact of the matter is, if the right product is specified for the right application, then the desired savings will be achieved naturally. Using the right control device extends the life of a motor, along with those of the mechanical components connected to it. Trying to solve every application using one type of product is like trying to eat all varieties of food with a fork. While it may be the best tool for many foods, it certainly wouldn’t work well with a bowl of soup. This applies to areas other than motors. Many users believe that pumps need to run at full speed all of the time because processes further down the line can handle any excess flows easily, or they have control valves in place. This will not prove to be the most cost- effective or energy-efficient approach. Using a drive or soft-start allows users to limit the pump speed to produce the required flow, or to match the flow to the process. To summarise: you need to consider whether everything you are currently using is doing its job to the best of its ability. If the answer is yes, then that’s fantastic, but if not, then look at whether you can use what you already have better? The answer may be to install new or upgraded equipment, but at least there will be a justifiable reason behind this decision. n “Using the right equipment for the right application is vital. Nearly all factories have a variety of drives, motors, relays, switches and more, yet are we certain that the correct products are being used for the correct applications?” Before installing new equipment in your plant, or upgrading existing, equipment, you need to ask what you are trying to achieve. Nikesh Mistry*, Gambica’s sector head for industrial automation, argues that often you just need to use your existing equipment better. Do you need to buy new equipment? Or just use your existing kit better? * Gambica is the trade association for the automation, control, instrumentation and laboratory technology sectors in the UK. For more information, please contact NikeshMistry on 020 7642 8094 or via nikesh.mistry@gambica.org.uk