专业外语教学资料 专业英语－10 introduction of programmable controllers讲义教材.pptVIP

English in Electric Automation;solenoid [ s?ulin?id ] n.线圈 stand-alone adj. 独立的 stepper [ step? ] n.步进电机 subnet [ s?b.net ] n.子网 thermocouple [‘θ?:m?u.k?pl] n. 热电偶 troubleshoot v. 排除故障 uninterruptible power supply 不间断电源（UPS） vendor [ vend?: ] n. 生产厂商 vibration [ vaibrei??n ] n.震动 water –tight 防水 wreak [ ri:k ]? v.发泄，报复 (control)panel 控制（继电器）柜 field device 现场设备;These devices, commonly known as relays, were being used by the thousands to control many sequential- type manufacturing processes and stand-alone machines. 这些通常称为继电器的设备被数以千计的人用来控制许多顺序制造过程和单独机器。 But the common applications for relay panels called for 300 to 500 or more relays, and the reliability and maintenance issues associated with supporting these panels became a very great challenge. 但是，继电器柜的常规应用需要300到500或更多继电器，可靠性和支持这些柜的维护问题成为一个很大的挑战。 called for 要求;To make mattes worse, the constantly changing needs of a process called for recurring modifications of a control panel. With relays, this was a costly prospect, as it was accomplished by a major rewiring effort on the panel. In addition, these changes were sometimes poorly documented, causing a second-shift maintenance nightmare months later. 更糟糕的是，控制过程需要经常性的改变，这要求对继电器柜重新修改，由于这种修改是通过对继电器柜的主要连线进行重新连接而成，这意味着更多的费用。此外，这些改变没有经过足够的验证，因而数月后，又导致了二次布线改变维护的噩梦。;In light of this, it was not uncommon to discard an entire control panel in favor of a new one with the appropriate components wired in a manner suited for the new process. Add to this the unpredictable, and potentially high, cost of maintaining these systems as on high-volume motor vehicle production lines, and it became clear that something was needed to improve the control process - to make it more reliable, easier to troubleshoot, and more adaptable to changing control needs. 在这种情况下，放弃整个控制柜而选用新的、具有正确连线且适合于新的控制过程的控制柜的做法并不少见。对于大产量的机动车辆生产线，加上这一无法预料、潜在的高维护费用，很明显，需要对控制过程进行改进——使其更可靠、更易于进行故障检修，以及更易于适应控制需求的改变。 ;That som