RELANCE 61C350 模拟导轨模块
dcs的定义 dcs是分布式控制系统(distributed control system)的简称,亦称为集散控制系统,它是由回路仪表控制系统发展而来,是在计算机、通讯、控制和crt技术迅速发展的基础上产生的。 3.2 dcs的发展历程 上世纪60年代以后,随着生产工程的大型化和复杂化,诞生了计算机集中监视和控制的集中控制系统。集中控制方便了监视、操作和管理,同样也使危险性高度集中,系统一旦故障,对装置造成的影响和危险性都是非常大的。随着微处理机的诞生,为新型控制系统的开放创造了无比优越的条件。1975年,随着计算机、通讯、控制和crt 4c技术的不断发展和完善,美国honeywell首次向全球推出了分散控制系统tdc-2000,从第一套dcs诞生至今,dcs系统已经经历了3个发展阶段。 1975至1980年为初创阶段。由于软硬件技术的限制,此时的dcs系统性能还不十分完善,硬件结构还不十分成熟。 1981至1987年为第2个阶段。这一时期容错、冗余技术已经成熟使用,系统可靠性很高,性能十分优越,各种控制功能十分丰富。在该阶段dcs从单纯的工业过程自动化控制向生产管理自动化发展。这一代的dcs主要将lan(local area network)技术引入,使dcs的网络功能大大加强。
上世纪70年代,由于经济的迅速发展,生产装置迅速向大型化方向发展,尤其是石油炼制、冶金、化工、建材、电力等行业,这些行业生产装置的大型化能够带来明显的好处,如生产效率提高、原料消耗减少、劳动力成本降低等。生产设施的大型化要求设备之间具有更好的协调性,而且停机将带来更大的损失。因此用户迫切希望能够有一种产品或者系统能够解决生产设施大型化和连续化所面临的控制问题。与此同时,在20世纪70年代中期,大规模集成电路取得突破性的发展,8位微处理器得到了广泛的运用,使自动化仪表工业发生巨大的变化,现代意义上的DCS也应运而生,1975年Honeywell推出了第一个DCS产品。 中国使用DCS始于1981年,当时吉化公司化肥厂在合成氨装置中引进了Yokogawa的产品,表现出良好的控制性能和可靠性。随后中国引进的30套大化肥项目和大型炼油项目都采用了DCS控制系统,提高了生产设施的效率和产品质量的连续性,并且物耗和能耗也有不同程度的降低。DCS产品在石油和化工行业的成功应用也促进了其他行业控制系统的发展,在随后的几年,冶金、建材、电力、轻工等行业的新建项目中也陆续使用了DCS产品,并成为这些行业的主流控制系统。
Pay attention to the situation where all operating stations are powered off
At this time, check if the power indicator light of the control station is normal, and if there is a fault in the card diagnosis indicator light. The red light and green light indicate that the card is working normally. If all of the above are normal, it can be determined that the control station is working normally and the self adjustment system is working normally. However, the operator cannot see the monitoring screen temporarily and cannot perform remote control operations on site. Immediately notify the microcomputer maintenance personnel to repair and go to the site for monitoring.
Pay attention to the situation where all control stations are powered off
Due to the dual power supply of all control station equipment, one UPS and one mains power supply, the probability of this situation occurring is very low.
When the control station is completely powered off, the two system alarm red lights on the monitoring screen light up, communication is interrupted, and all data is not refreshed. All self regulating systems are completely out of control, and the regulating valve will return to its initial state. The air opening valve will be fully closed, and the air closing valve will be fully open. At this time, emergency handling or parking should be carried out immediately, and the operation should be carried out on-site at the same time.
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① Allen Bradley (USA AB) series products
② Schneider series products
③ General Electric series products
④ Westinghouse Series Products
⑤ SIEMENS (Siemens series products)
⑥ Selling ABB Robots FANUC Robots, YASKAWA Robots, KUKA Robots, Mitsubishi Robots, OTC Robots, Panasonic Robots, MOTOMAN Robots.
⑦ Westinghouse: OVATION system, WDPF system, MAX0 system spare parts.
⑧ Invensys Foxboro: I/A Series system, FBM (Field Input/Output Module) sequential control, trapezoidal logic control, accident memory processing, analog-to-digital conversion, input/output signal processing, data communication and processing, etc. Invensys Triconex: Redundant fault-tolerant control system, modern fault-tolerant controller based on Triple Modular Redundancy (TMR) structure.
⑨ Siemens: Siemens MOORE, Siemens Simatic C1, Siemens CNC system, etc.
⑩ Bosch Rexroth: Indramat, I/O modules, PLC controllers, drive modules, etc.
◆ Motorola: MVME 162, MVME 167, MVME1772, MVME177 and other series.
PLC module, programmable controller, CPU module, IO module, DO module, AI module, DI module, network communication module,
Ethernet module, motion control module, analog input module, analog output module, digital input module, digital output module
Module, redundant module, power module, relay output module, relay input module, processor module.
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