In the process of designing systems that ensure production tasks, many operational nuances are taken into account. Each complex is individual, but the principles of its implementation are based on a basic set of requirements. The system must be efficient, reliable, functional and at the same time ergonomic. The link between directly the technical part of production support and control tasks is implemented by controllers for process automation. They concentrate information coming from different technological sectors, which acts as the basis for making certain decisions.
Application classification of controllers
Almost every modern enterprise to some extent uses systems that automate workflows. Moreover, the nature of the functions served can be completely different. So, in the chemical industry, programmable equipment through the controllers controls the dosing, supply volumes of bulk and liquid materials, monitors the properties of various substances using sensors, etc. In the service sector of transport organizations, the emphasis is on the management of power equipment, as a rule, loading and unloading. Universal controllers for automation of ventilation, heating and water supply systems are also widespread. This is a group of systems that manage engineering and public utilities in enterprises in various fields. Conversely, there are highly specialized areas in which it is necessary to individually develop systems for specific needs. These areas include the oil industry and metallurgical plants.
The principle of operation of the controllers
An industrial controller is a microprocessor that provides hardware and software. The first part, in fact, serves the physical work of a system based on an embedded task execution program. An important aspect of any configuration of this type is the regulatory infrastructure. That is, the software basis is responsible for making certain decisions, but in the future the received signals are sent to the points of the commands given directly to the working equipment. Thus, controllers for automation control machines, conveyor lines, technical power tools, etc.
Another equally important component of the overall management infrastructure are sensors and indicators, on the basis of which the controller develops decisions or strategic chains that determine the operating modes of the equipment. This can be sensors that assess the condition of apparatus and assemblies, materials served, microclimate parameters in the production room and other characteristics.
Automation Controller Architecture
The architecture of the controller is understood as a set of components, due to which the automation control function is implemented. As a rule, the architectural configuration assumes the presence of a processor, network interfaces, a storage device and input-output systems in the complex. This is the basic equipment, but depending on the needs of a particular project, the composition and characteristics of individual parts may vary. Sophisticated controllers for automation are called modular. If the traditional simple architecture is a unified block with a typical composition of functional elements that are not accessible for change by the operator, then in complex architectural models a multicomponent modular configuration is implemented. It allows not just the maintenance of a single closed unit, but also each module individually. Now it is worth considering the individual parts of the architecture in more detail.
Types of architecture modules
The basic modular device is a microprocessor. From its power depends on how complex the tasks performed by a particular controller can be. The storage device also matters. It can be integrated into the system without the possibility of further changes. But most often, external flash memory modules are used, which can be completely changed depending on current tasks. The responsibility for the actions that industrial automation controllers take is largely vested in I / O devices. Through these channels, the processor receives information for processing and subsequently gives the appropriate commands. In modern complexes, interface modules play an increasingly important role, on which the controller's communication capabilities depend.
The main characteristics of the processor module
When developing a control system, it is especially important to consider the basic characteristics and capabilities of the microprocessor. As for the main operating parameters of this module, these include the clock frequency, bit capacity, periods of tasks, memory, etc. But even these characteristics do not always become decisive, since the performance indicators of modern even budget microprocessors are enough to service most of the production processes. It is much more important to determine the communication capabilities and functions that controllers perform to automate the work of the enterprise. In particular, in the first place according to requirements, operators put the ability to work with a wide range of network channels, interfaces and programming languages. Separately, it is worth noting the ability to connect display devices, controls, modern displays and other components.
Operator panel
Regardless of the characteristics of the controller's filling, an operator station with an appropriate relay must be provided for controlling its functions. Outwardly, such devices resemble a small computer, provided with input and output devices, process sensors and a display. The simplest controllers for automation of production include the ability to program through this panel. Moreover, programming may mean elementary settings of entry-level commands. The most sophisticated operator panels also perform self-diagnosis and self-calibration.
Automation System Power Supplies
The average voltage range supplying industrial controllers is in the range of 12-48 V. The source is usually a local 220V network. Moreover, the power supply is not always in proximity to the equipment being serviced. For example, if controllers are used to automate a boiler room in a multi-stage metallurgical production, then a distributed power supply network can be equidistant from several energy consumers. That is, one circuit will serve the boiler for soft metals, and the other for hard ones. Moreover, the voltage may change in the lines.
Conclusion
Automation systems for work processes are increasingly becoming part of the infrastructure of modern enterprises. Accordingly, controllers for automation systems in various modifications are widely used. The content of such a device itself does not require special expenses. The main difficulties in working with this equipment relate to the quality of programming and optimization of the configuration layout. But at the same time, to simplify operator functions, modules are also becoming more popular, involving self-tuning according to the basic data entered by the user.