RELANCE 57C431 電源
DCS控制系統(tǒng)在實(shí)際生產(chǎn)應(yīng)用中有很多企業(yè)，特別是電廠、冶煉廠等，其廠區(qū)內(nèi)有一個(gè)很大的地線網(wǎng)，而通常供電系統(tǒng)的地是與地線網(wǎng)連在一起的。有的廠家強(qiáng)調(diào)計(jì)算機(jī)系統(tǒng)的所有接地必須和供電系統(tǒng)地以及其它（如避雷地）嚴(yán)格分開，而且之間至少應(yīng)保持15m以上的距離。為了徹底防止供電系統(tǒng)地的影響，建議供電線線路用隔離變壓器隔開。這對那些電力負(fù)荷很重，而且負(fù)荷經(jīng)常啟停的單位是應(yīng)注意的。
從抑制干擾的角度來看，將電力系統(tǒng)地和計(jì)算機(jī)系統(tǒng)的所有地分開是很有好處的，因?yàn)橐话汶娏ο到y(tǒng)的地線是不太干凈的。但從工程角度來看，在有些場合下單設(shè)計(jì)算機(jī)系統(tǒng)地并保證其與供電系統(tǒng)地隔開一定距離是很困難的，這時(shí)可以考慮能否將計(jì)算機(jī)系統(tǒng)的地和供電地共用一個(gè)，這要考慮幾個(gè)因素：
二、供電系統(tǒng)地的接地電阻是否足夠小，而且整個(gè)地網(wǎng)各個(gè)部分的電位差是否很小，即地網(wǎng)的各部分之間是否阻值很?。ǎ?W）
三、DCS的抗干擾能力以及所用到的傳輸信號的抗干擾能力，例如有無小信號(電偶，熱電阻）的直接傳輸?shù)取?/span>
上世紀(jì)70年代，由于經(jīng)濟(jì)的迅速發(fā)展，生產(chǎn)裝置迅速向大型化方向發(fā)展，尤其是石油煉制、冶金、化工、建材、電力等行業(yè)，這些行業(yè)生產(chǎn)裝置的大型化能夠帶來明顯的好處，如生產(chǎn)效率提高、原料消耗減少、勞動(dòng)力成本降低等。生產(chǎn)設(shè)施的大型化要求設(shè)備之間具有更好的協(xié)調(diào)性，而且停機(jī)將帶來更大的損失。因此用戶迫切希望能夠有一種產(chǎn)品或者系統(tǒng)能夠解決生產(chǎn)設(shè)施大型化和連續(xù)化所面臨的控制問題。與此同時(shí)，在20世紀(jì)70年代中期，大規(guī)模集成電路取得突破性的發(fā)展，8位微處理器得到了廣泛的運(yùn)用，使自動(dòng)化儀表工業(yè)發(fā)生巨大的變化，現(xiàn)代意義上的DCS也應(yīng)運(yùn)而生，1975年Honeywell推出了第一個(gè)DCS產(chǎn)品。 中國使用DCS始于1981年，當(dāng)時(shí)吉化公司化肥廠在合成氨裝置中引進(jìn)了Yokogawa的產(chǎn)品，表現(xiàn)出良好的控制性能和可靠性。隨后中國引進(jìn)的30套大化肥項(xiàng)目和大型煉油項(xiàng)目都采用了DCS控制系統(tǒng)，提高了生產(chǎn)設(shè)施的效率和產(chǎn)品質(zhì)量的連續(xù)性，并且物耗和能耗也有不同程度的降低。DCS產(chǎn)品在石油和化工行業(yè)的成功應(yīng)用也促進(jìn)了其他行業(yè)控制系統(tǒng)的發(fā)展，在隨后的幾年，冶金、建材、電力、輕工等行業(yè)的新建項(xiàng)目中也陸續(xù)使用了DCS產(chǎn)品，并成為這些行業(yè)的主流控制系統(tǒng)。
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.