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诞生于20世纪60年代的PLC始终处于工业控制自动化领域的主战场,以其控制方便、可靠性高、容易掌握、体积小和价格适宜等特点,广泛应用于航天、冶金、轻工及建材等行业,满足企业对自动化的需要。在欧美等发达国家,PLC在工业自动化总产值中占据了70%以上的份额,世界平均水平也在50%左右,而我国仅三成。随着量大面广的设备进行自动化改造,我国PLC应用进入高速发展期,在未来5～10年内年增长率将超过20%。目前国内PLC形成市场规模的企业没有一家,市场基本为国外公司所垄断。虽然近年来以和利时、安控为代表的企业取得了一定的成效,但实力还远不济,本土企业还待继续努力,争取早日能有几家本士企业能与国外公司抗衡,把PLC高昂的价格打压下来。随着微处理器、网络通信、人—机界面技术的迅速发展,工业自动化技术日新月异。PLC由最初的只能处理开关量而发展到可以处理模拟量和数据等,加之与DCS、PID、工业PC等技术相结合,使之不再是一种简单的控制设备。PLC将随着自动控制技术的不断发展而发展下去,集成化、微型化、网络化、PC化和开放性是PLC发展的主要方向。
Born in the 1960s, PLC has always been the main battlefield in the field of industrial control automation. It is widely used in aerospace, metallurgy, light industry and building materials for its convenient control, high reliability, easy to grasp, small size and suitable price. Industry, to meet the business needs of automation. In developed countries such as Europe and the United States, PLC accounts for more than 70% of the total industrial output value. The world average is also around 50%, while in our country only 30%. With the large volume of equipment for automation transformation, PLC applications in China entered a period of rapid development in the next 5 to 10 years annual growth rate will exceed 20%. At present, there is not one enterprise that has formed a market scale in China, and the market is dominated by foreign companies. Although in recent years, the companies represented by Lee and Amco have achieved some success but their power is still far from being good. Local enterprises are yet to continue their efforts to win several Bomb enterprises as soon as possible to compete with foreign companies. PLC High prices suppressed. With the rapid development of microprocessors, network communications and human-machine interface technologies, industrial automation technology is rapidly changing. PLC from the initial can only handle the switch and can be developed to handle analog and data, combined with DCS, PID, industrial PC and other technologies combine to make it no longer a simple control device. PLC will continue to develop with the automatic control technology continues to develop, integration, miniaturization, networking, PC-based and open is the main direction of the development of PLC.