Programmable Automation Programming of logical controllers

Logical controllers' programming 1.1- Generalities All the Technicians, that they developed in the automation through cables, that is, I entrust the thread, they are today the first and big enthusiasts of this new technology computer science. In fact, those Professionals, a lot of times faced great obstacles, depressions and other problems for lack of functions or instructions that nowadays are within reach of any logical controller.

Logical controllers' programming 1.1- Generalities Many Technicians affirm, with conviction, that until it seems impossible the easiness with that it can project an automatic system now. Today, I control it of individualized machines or together, or still, the supervision and administration of a complete unit of production, have for base the programmable logical controller.

Logical controllers' programming 1.1- Generalities As tool comes to create a new philosophy before the old difficulties, because in the practice, that “black box” it executes all our requests or demands to the point of we could affirm that the scheduled automation only depends on the human imagination. This new instrument can be faced as a “block of notes” emptiness where we scored “everything” that that very well understand and that later on answers us in a logical way when we sent our requests or information.

Logical controllers' programming 1.2- Concepts PLC (PLC: programmable logic controller )

Logical controllers' programming 1.2- Concepts It is an electronic equipment; programmable in language non computer science; conceived to control in real time and in industrial atmospheres, sequence processes. CONCEPT OF PLC The industrial programmable controller (PLC: programmable logic controller )

Logical controllers' programming 1.3- Constitution In a simple way, we can consider the programmable logical controller as a device that processes information and whose constitution understands the following:  Central unit of Processing (CPU)  Modules of Entrances (Inputs)  Modules of Exits (Outputs)  Special modules  Communication capacity

Logical controllers' programming CPU Habitually, its potentiality is it measured for the number of entrances and exits that it controls; Even so, it is indispensable to analyze the maximum capacity of address of programs; Ascending and descending accountants; Timers and bases of time; Areas of special bits;  Central unit of Processing (CPU) It is that the one that calls her–the controller's memory.

Logical controllers' programming CPU and above all, the group of programming instructions, like for example:  Central unit of Processing (CPU)  Instructions of Transfer of Data  Instructions of Comparison  Arithmetic instructions in BCD (Binary coded decimal)  Basic instructions  Logical instructions  Special instructions

Logical controllers' programming CPU Another subject not less important it is the time that the controller needs, for to run every program. This depends on the number of instructions that they constitute the program and of the partial time of processing for each instruction. Usually, the logical controllers' makers indicate values among bad 30 and 0,4 for 1 K of instructions (1 K = 1024 instructions). These are medium values, being destined 80% at basic instructions and 20% to processing of data  Central unit of Processing (CPU)

Logical controllers' programming Entrances They are destined to the acquisition of arrived signs of the exterior. These can be binary or analogical and in the future they will be “fuzzy” (vacated or diffuse). The logic “fuzzy”, it was developed to turn the computers capable to flee to the binary logic traditional that just admits two logical values: False / true, black / white, zero / one.  Modules of Entrances (Inputs)

Logical controllers' programming Entrances  Modules of Entrances (Inputs)

Logical controllers' programming Exits They drive the signs destined to the outputs after all the information internally to have been processed by the Central Unit. The digital modules can be the relay, transístor or triac The exits the relé is usually favorite because most of the time they release the joining relés to the actuadores.  Modules of Exits (Outputs)

Logical controllers' programming Exits  Modules of Exits (Outputs)

Logical controllers' programming Modules They are destined for example to the positioning of an or more axes in a motor step-to-step or to recognize signs of high frequency, as:  generators of pulses (encoders);  photocells that generate signs whose period is of milliseconds and that difficultly can be seen in the normal considered entrances.  Special modules

Logical controllers' programming Communication With relationship to the communication, the common user can establish “dialogue “with the controller through one consoles, with appropriate keyboard or through a computer. The logical controllers, communicate with the computer by means of modules of “interface”, changing telegrams, whose content defines the area to reach, as well as the data that it receives or that sends.  Communication capacity

Logical controllers' programming Communication The capacity to communicate admits other levels, as the communication in net, where the logical controllers join through units of joining. Even so, when the user communicates with the controller, he will have that doing through a language that it understands. There is, in fact, several programming languages as: Boollean, ladder Diagram, Functional or Logical, High level, and Grafcet.  Communication capacity

Logical controllers' programming Summary a logical controller is: In summary and in scheme form PROCESSOR CPU OUTLYING POWER SIGNS FOR RECEIVERS SIGNS OF SENSOR E S MEMORY

Logical controllers' programming Peripherals peripherals