In order to eliminate the interference of the inverter to the dcs signal,we have taken the following measures,making the grounding wire thicker and making the grounding point as close to the inverter as possible;Ground the steel pipe reliably.Through the above measures,the frequency of oop alarm in dcs has been significantly reduced,but the interference of the inverter has not been completely eliminated.Could it be the fault of the inverter?We replaced the inverter for this,and the interference signal was eliminated immediately.Just when we thought the problem was completely solved,the glitch reappeared a month later.So far,the fault point has not been replaced except the signal line from the inverter to the dcs,other components have been replaced.Therefore,we replaced the shielded signal line,and the fault was completely solved.
为了消除变频器对dcs信号的干扰,我们采取了如下措施,将接地线加粗并将接地点尽量靠近变频器;同时,将变频器送dcs的信号线在变频器出线侧穿钢管敷设,并将钢管可靠接地。通过以上措施,dcs出现oop报警的频率明显降低,但仍未能彻底消除变频器干扰。会不会是变频器故障呢?为此我们更换了变频器,干扰信号马上消除。就当我们以为彻底解决问题的时候,该故障又在一个月后出现。至此,该故障点除了变频器至dcs的信号线未更换,其他元器件都已经更换过。于是,我们将该屏蔽信号线进行了更换,结果故障得到了彻底解决。
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