How to ensure EMC of the PAC (Power Controller Assembly) motion bus?

Ensuring the EMC of the PAC motion bus (such as EtherCAT, PROFINET IRT) of the intelligent controller requires attention to interface protection, wiring, and shielding. Shielded connectors are used for the interface, with internal common-mode inductors (CMZ3225A-510T) and TVS arrays (ESDLC3V3D3B). Differential pairs are used in the wiring, with strict equal length and spacing, referencing a complete ground plane.

Shielded twisted-pair cables are used, with 360-degree termination of the shielding layer. The power supply is independent for the PHY chip, with filtering using a ferrite bead (PBZ1608A-102Z0T). During testing, the motion bus must pass IEC61000-4-2 ESD 8kV, IEC61000-4-4 EFT 4kV, and IEC61000-4-5 Surge 2kV tests, with a communication error rate below 10^-10, meeting the IEC61800-3 standard.