plc analog input modules of the main features of some other

In the industrial production process, a large amount of sequence control switch, which follow a logical sequence of actions conditions and controlled chain protection action in accordance with the logic, and a large number of discrete data collection. Traditionally, these functions plc communication modules  are controlled by pneumatic or electrical system to achieve the second year, based on the control unit integrated circuits and electronic technology, for the first time using procedural methods used in electrical control, this is the first generation of programmable logic controller , called Programmable ontroller (PC). After a personal computer (the PC) to develop, for convenience, but also to reflect the features of programmable controllers, programmable logic controller named Programmable Logic Controller (PLC).
Growth rate has been maintained at 30 to 40%. During this period, PLC analog processing capacity, number-crunching, man-machine  plc sequence of events recording module interface capabilities and network capacity has been greatly improved, PLC gradually entering the field of process control, replaced in some applications in the field of process control in a dominant DCS systems. PLC has the versatility, ease of use, wide adaptation, high reliability, strong anti-jamming capability, programming and simple. PLC in the industrial automation and control especially in order to control the position, in the foreseeable future, can not be replaced.