How to reduce coupling when routing I/O module cables?

The key to reducing coupling interference between I/O module cables lies in scientific cable routing planning. First, cables should be classified and grouped according to different categories: high-voltage power cables, low-voltage control cables, analog signal cables, communication cables, etc. Cables in different groups should be laid separately, using independent cable trays or maintaining sufficient spacing; for example, the distance between power cables and control cables should be greater than 30cm. Within the same group, cables from different circuits should also be separated as much as possible or cross perpendicularly. All cables should be laid as close as possible to grounded metal surfaces, such as cabinet walls or metal cable trays, to utilize the mirror effect to reduce radiation.

Avoid forming large loops in the cables; power lines and return lines should be kept close together. Cables should avoid running parallel to equipment that generates strong magnetic fields, such as transformers and motors. For sensitive signal cables, metal conduits can be used to provide additional shielding. During the planning phase, a cable routing diagram should be drawn, indicating the path and spacing requirements for each type of cable. After construction, a clamp meter can be used to measure the induced current on the cables, or a near-field probe can be used to test the coupling strength to verify the effectiveness of the routing.