RELANCE 57C431 电源

DCS控制系统在实际生产应用中有很多企业，特别是电厂、冶炼厂等，其厂区内有一个很大的地线网，而通常供电系统的地是与地线网连在一起的。有的厂家强调计算机系统的所有接地必须和供电系统地以及其它（如避雷地）严格分开，而且之间至少应保持15m以上的距离。为了彻底防止供电系统地的影响，建议供电线线路用隔离变压器隔开。这对那些电力负荷很重，而且负荷经常启停的单位是应注意的。

    从抑制干扰的角度来看，将电力系统地和计算机系统的所有地分开是很有好处的，因为一般电力系统的地线是不太干净的。但从工程角度来看，在有些场合下单设计算机系统地并保证其与供电系统地隔开一定距离是很困难的，这时可以考虑能否将计算机系统的地和供电地共用一个，这要考虑几个因素：

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.

Here are our main products. If you need them, we can send them to help you compare the prices!

Main business: World brand PLC and DCS system spare parts modules

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.

Our advantage is: brand new original, with a one-year warranty! All products of our company have undergone strict testing. We welcome inquiries and acquisitions. As long as you have sincerity, our company will provide you with a price advantage over peers and work together to win the order.