Since the automation industry comprises fairly large and mature companies with highly technical processes, this reflects on the manpower needs as well. The skill requirements are vast and there is room for professionals for product design and development, sales, project engineering, product management, marketing and sales. Professionals who have a superior understanding of electronics, instrumentation, electrical, mechanical and robotics engineering are required among others.
Automation is a very technical field and therefore domain expertise and knowledge of processes is very important. Because of the technology-driven nature of this field, professionals must at all times keep themselves abreast of the latest improvements and technological upgradations that are taking place, instead of narrowly focusing on their departmental concerns.
In additional to technical skills, recruiters are looking for such competencies as interpersonal skills and drive for end results down the ranks. Don’t get nervous. You are not expected to know everything but your learn-ability levels should be high as a lot of training would essentially take place on the job.
Next, let me share some basics of automation beyond programmable logic control (PLC) and SCADA.
How to control the control loop?
Keep in mind that automation is the use of control systems (such as numerical control, programmable logic control and other industrial control systems), along with other applications of information technology (such as computer-aided design and computer-aided manufacturing), to control industrial machinery and processes, thereby reducing the need for human intervention.
A simple process control loop consists of three elements: a measurement system, a controller and a final control element. With regards to industrialisation, automation is a step beyond mechanisation. While mechanisation provided human operators with machinery to assist them in the physical requirements of their work, automation greatly reduces the human sensory and mental requirements. It refers to a wide range of hardware and software products and protocols used to communicate between standard computer platforms (PC, Macintosh or workstation) and devices used in industrial automation applications such as controllers.
Before the advent of computers, controllers were usually single-loop proportional-integral-derivative (PID) controllers. These were used to execute PID control functions. These days, the controllers can do a lot more, however, 80 to 90 per cent of the controllers used in India are still PID controllers. Digital controllers do not have mechanical moving parts. Instead, these use processors to calculate the output based on the measured values. Since they do not have moving parts, they are not susceptible to wear and tear with time. However, digital controllers are not continuous.
Understand the controllers from both the theoretical and practical point of view. Forget the analogue versus digital controversy. Both types of controllers have their respective pros and cons. Analogue controllers are based on mechanical parts that cause changes to the process via the final control element. Again, like final control elements, these moving parts are subjected to wear and tear over time and that causes the response of the process to be somewhat different with time. But analogue controllers control continuously.
The next thing you need to know is the measurement system. In the context of process control, controller decisions are based on measurements of process parameters. With the advent of computers, it is now possible to do inferential measurements, which means telling the value of a parameter without actually measuring it physically. It should, however, be remembered that inferential measurement algorithms are also based on physical measurements. Therefore, rather than rendering measurements redundant, they have made measurements all the more important.
Final control elements can refer to three things: control valves, variable-speed drives and dampers. In process plants, more often than not, the final control element is the control valve.
The automation industry is growing 6-8 per cent globally, whereas in countries like india and China, it is growing at more than 30 per cent
The issues relating to final control elements are most relevant to control valves, although these are applicable to a large extent to dampers and in some cases variable-speed drives as well. So try to get a clear idea about the instrumentation part of the control valve.
How to standardise the control?
For starters, learn to use OPC—‘OLE (object linking and embedding technology) for process control.’ It is a series of standards’ specifications. The first standard—originally called the OPC specification and now the Data Access specification—resulted from the collaboration of a number of leading worldwide automation suppliers working in cooperation with Microsoft. Originally based on Microsoft’s OLE COM (component object model) and DCOM (distributed component object model) technologies, the specification defined a standard set of objects, interfaces and methods for use in process control and manufacturing automation applications to facilitate interoperability.