P0926GX熱電阻模塊,FOXBORO實(shí)驗(yàn)數(shù)據(jù)P0926GX
信號(hào)程度如果超過(guò)規(guī)定范圍也會(huì)對(duì)系統(tǒng)產(chǎn)生影響。為了保證在大型電機(jī)進(jìn)行開(kāi)關(guān)時(shí)對(duì)系統(tǒng)進(jìn)行保護(hù)，可以采用在電路中加入變壓器，保證在開(kāi)關(guān)電機(jī)時(shí)不會(huì)因?yàn)殡妷鹤兓^(guò)大而產(chǎn)生交變磁場(chǎng)。P0926GX
造成干擾的主要原因？材料及設(shè)備問(wèn)題
接入DCS系統(tǒng)的控制信號(hào)通常采用電纜作為傳輸介質(zhì)將信號(hào)送至DCS系統(tǒng)，當(dāng)信號(hào)電纜絕緣材料老化，屏蔽材質(zhì)損壞，即會(huì)被其他電磁干擾源干擾，干擾會(huì)造成測(cè)量的誤差，嚴(yán)重的干擾會(huì)造成設(shè)備損壞。施工不規(guī)范
在DCS控制系統(tǒng)中，往往有很多信號(hào)同時(shí)接入DCS。這些信號(hào)線(xiàn)或者走電纜槽，或者走電纜管，造成現(xiàn)場(chǎng)很多不同種類(lèi)電纜在同一個(gè)路徑附設(shè)。這些信號(hào)之間均有分布電容存在，會(huì)通過(guò)這些分布電容將干擾加到別的信號(hào)線(xiàn)上。同時(shí)，在傳輸信號(hào)的周?chē)h(huán)境產(chǎn)生交變的磁通，例如動(dòng)力線(xiàn)、電動(dòng)機(jī)、發(fā)電機(jī)、電源變壓器和繼電器等都會(huì)產(chǎn)生這種磁場(chǎng)。這些磁場(chǎng)往往會(huì)造成較大的干擾。
接地不合理P0926GX熱電阻模塊,FOXBORO實(shí)驗(yàn)數(shù)據(jù)P0926GX
比較常見(jiàn)的接地事故是信號(hào)線(xiàn)的兩端均接地，這樣會(huì)因地電勢(shì)差而產(chǎn)生較大的干擾。如信號(hào)線(xiàn)的兩端同時(shí)接地，可能會(huì)有較大的電位差，這種電位差可能會(huì)在兩端之間的信號(hào)線(xiàn)上產(chǎn)生一個(gè)很大的環(huán)流。產(chǎn)生電磁波，干擾信號(hào)。還有DCS系統(tǒng)總接地電阻不符合DCS系統(tǒng)正常工作要求等等。
如何抑制干擾？
保證信號(hào)線(xiàn)正常使用
在信號(hào)線(xiàn)的使用過(guò)程中，避免多條信號(hào)線(xiàn)糾纏在一起，同時(shí)定期對(duì)信號(hào)線(xiàn)進(jìn)行檢查，對(duì)有絕緣膠體有破損的信號(hào)線(xiàn)進(jìn)行修復(fù)和更換，以保證信號(hào)線(xiàn)的正常使用，避免發(fā)生漏電而對(duì)傳輸信號(hào)產(chǎn)生干擾。
將電纜分層敷設(shè)peripheral components such as pressure switch and solenoid valve during normal operation of the unit, so as to improve the safety factor of the whole device. Add the memory function of the first cause of the bending machine to help the operators know the first cause of shutdown at the first time, so as to avoid that there are multiple alarm indications on the previous or display panel, and the first cause can not be analyzed, or the first cause can not be found when the indicator light goes out with the instantaneous change of the on-site situation. At the same time, the existence of this function also provides a verification means for the record of accident recall system (SOE). This function can be completed by programming without adding any hardware equipment, and the programming skills are fully applied. When there is no shutdown condition, this function does not need to be executed and does not occupy the time of system monitoring, so that the monitoring and
