In one of our recent panel upgrades on a water treatment line, we noticed persistent EMI noise causing random signal glitches on some sensors. After double-checking wiring routes and shielding, the key fix turned out to be improving the grounding scheme. Adding a dedicated low-impedance ground bus inside the panel, plus ensuring cable shields were properly terminated at one end only, made a big difference. It also helped to segregate power and control wiring conduits to minimize interference. Curious if anyone else has seen noticeable signal stability improvements just from revisiting grounding and cable organization rather than swapping components? What grounding details often get overlooked in your field setups?
We’ve seen similar noise symptoms, but in our case the biggest improvement came from bonding all panel doors and gland plates back to the main earth point. Floating doors and poorly bonded cable glands were acting like antennas, especially on VFD-heavy panels. Another detail that often gets missed is the quality of the earth connection itself—painted surfaces or loose lugs can undo an otherwise good grounding design. For analog signals, adding a defined reference ground at the PLC end helped stabilize readings more than extra filtering. Have you ever traced EMI issues back to panel hardware bonding rather than cable routing, and do you test earth continuity as part of commissioning or only during troubleshooting?