ELECTRICAL AUTOMATION : EXPLAINS ABOUT PLCs AND ITS FUTURE In olden days for controlling the manufacturing processes relays were used. Because of excessive consumption of power it is difficult to figure out the linked problems with it, therefore it must be regularly replaced. To solve the problems, Programmable Logic Controller was unveiled. For more information join the electrical automation course to make your career in this field.
DEFINE PLC For the automation of different electro-mechanical processes in industries a digital computer called Programmable Logic Controller (PLC) is used. For surviving during tough times these controllers are specially used and they are protected from cold, heat, dust, and moisture, etc. Computer Language is used for programming the microprocessor existing in the PLC. It is a computer written program and is PLC down-loadable via cable. In the nonvolatile memory of PLC these loaded programs are stored. For the user fed program the hard wired logic was exchanged during the change from relay control panels to PLC. For controlling and programming the PLC, Ladder Logic, a visual programing language was created.
PLC HARDWARE CPU, Memory, Input/Output, Power Supply Unit, and Programming device are the hardware components of a PLC system. CPU– For avoiding the errors the PLC controller is checked. Logic Operations, computer interface, arithmetic operations are some of the performed functions. Memory– CPU uses fixed data. In the operating system the data is permanently stored in the System (ROM). Status of Input and Output devices, values of timers, counters and other external device information are stored in RAM. I/O section– Sensors, switches are field devices that are tracked by the input section. O/P Section- Motors, lights, pumps, and solenoids are some of the devices Output has a a control on. Reduced Instruction Set Computer (RISC) is the basis for I/O ports. Power Supply– An isolated power supply is available in certain PLC. You can find most of the PLCs working at 220VAC or 24VDC. Programming device– Inside the memory of the processor, the device is used for feeding the program. First the programming device is fed with the program and the later forwarded to the PLC’s memory.