plc_基础原理----中英文翻译.doc
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plc_基础原理----中英文翻译,1.1 motivationprogrammable logic controllers (plc), a computing device invented by richard e. morley in 1968, have been widely used in industry including manufa...
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1.1 Motivation
Programmable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].
Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.
1.1动力
1968年,Richard E. Morley创造出了新一代工业控制装置可编程逻辑控制器(PLC),现在,PLC已经被广泛应用于工业领域,包括机械制造也、运输系统、化学过程设备、等许多其他领域。初期可编程控制器只是用一种类似于语言的软件逻辑于代替继电器硬件逻辑,并且使开发时间由6个月缩短到6天。
虽然计算机控制技术已经产生,但是PLC控制因为它的高性能、成本低、并且对恶劣的环境有很强的适应能力而在工业控制的广泛应用中保持优势。而且,尽管硬件的价格在逐渐下跌,据估计,根据Frost和Sullivan对PLC市场的调查研究表明,每年销售硬件的价格要比销售PLC的价格(一千五百万)至少多出八十亿美元。PLC的创造者Richard E. Morley十分肯定的认为目前PLC市场是一个价值五十亿的工业
Programmable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].
Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.
1.1动力
1968年,Richard E. Morley创造出了新一代工业控制装置可编程逻辑控制器(PLC),现在,PLC已经被广泛应用于工业领域,包括机械制造也、运输系统、化学过程设备、等许多其他领域。初期可编程控制器只是用一种类似于语言的软件逻辑于代替继电器硬件逻辑,并且使开发时间由6个月缩短到6天。
虽然计算机控制技术已经产生,但是PLC控制因为它的高性能、成本低、并且对恶劣的环境有很强的适应能力而在工业控制的广泛应用中保持优势。而且,尽管硬件的价格在逐渐下跌,据估计,根据Frost和Sullivan对PLC市场的调查研究表明,每年销售硬件的价格要比销售PLC的价格(一千五百万)至少多出八十亿美元。PLC的创造者Richard E. Morley十分肯定的认为目前PLC市场是一个价值五十亿的工业