Interference-induced temperature fluctuations in DCS systems
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This post was last edited by Tongfk on 2023-2-7 at 13:54. Dear experts, the DCS system in our facility uses platinum resistance sensors to measure temperatures. Currently, some of these sensors are affected by interference, with temperature fluctuations ranging from 2–3°C in magnitude or less than 1°C in smaller cases. We plan to reduce the extent of this interference by using grounding. Since the server cabinets are located on the third floor, we use the building’s equipotential bonding box for grounding, and this does help, but fluctuations still occur. How should we handle grounding on the third floor?
You might consider adding a signal manager to give it a try.
We all use individual grounding piles, and the resistance meets the requirements – OK
Will the long distance from the third floor to the first floor have an impact?
Hello, which signal manager?
I’m not saying that your original DCS cabinets aren’t grounded, right? It’s a good idea to measure the grounding resistance; also check the grounding resistance at the equipotential points. Of course, the ideal approach is to have a separate grounding conductor leading to the main grounding grid. If the main grounding grid isn’t of high quality, it’s possible to consider installing a separate set of grounding electrodes in an appropriate location. Whether it is appropriate to lead down from the third floor depends entirely on the cross-section and material of the grounding material used; in any case, the key criterion is the value of the grounding resistance, which should be less than 1 ohm.
I have a question: are the other instruments unaffected?
Where is the equipotential box for buildings connected to?
Without an external grounding grid, it is the building itself that provides grounding