Series of Posts on Preventing Common Problems in Instrument Installation (8)

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Series of Posts on Preventing Common Problems in Instrument Installation (8): We welcome fellow enthusiasts to actively participate in the discussion of these issues. Constructive suggestions will be rewarded generously; having relevant images will earn additional points as a bonus. By sharing such problems and their solutions, we can avoid similar issues arising in future installations and create a favorable environment for maintenance work. Thank you! Common problems in cable installation: 8. During cable laying, the AC power supply lines and instrument signal lines are placed in the same tray without being separated by a metal partition, or the instrument cables are located too close to devices that generate strong magnetic fields. l Analysis and prevention: l In the same cable tray, AC power lines and instrument signal lines should be laid separately using metal partitions; otherwise, the instrument signal lines will be affected by the power cables, and the strong magnetic and electrostatic fields from the AC power lines can cause static electricity to accumulate in the instrument control cables. When the instrument signal cable is a shielded cable or is run in a metal protective tube as well as in a covered metal cable tray, the clear distance from strong magnetic fields and strong electrostatic fields should be greater than 0.80 m. The clear distance between the instrument signal wires laid openly and strong magnetic fields as well as strong electrostatic fields should be greater than 1.50 m. Equipment such as high-voltage motors and exciters all belong to strong magnetic field devices.