How do frequency converters and PLCs coordinate their communication and EMC?

Achieving EMC coordination between the frequency converter and the PLC requires ensuring stable operation of both in a shared electromagnetic environment at the system level. Key design considerations for coordination include:

Interface protocol and hardware compatibility: both should use a consistent, interference-resistant physical layer, such as isolated RS485 or industrial Ethernet, and be configured with similar protection levels (TVS, common-mode choke).

Cable selection and grounding: connecting cables must use high-quality shielded twisted-pair cables, with the shield reliably grounded to the respective equipment chassis at both ends via shielding clips or connector metal shells, achieving a 360-degree overlap.

System grounding and equipotential bonding: the frequency converter cabinet and PLC cabinet should be connected to the same grounding busbar through low-impedance conductors to reduce ground potential difference.

Wiring separation: communication cables should be kept away from power cables, frequency converter output cables, and other strong interference sources; if unavoidable, they should cross perpendicularly.

Power supply considerations: if possible, the control power supplies for the PLC and frequency converter should ideally come from the same filtered power supply.

Software protocol: fully utilize the fault tolerance mechanisms of the communication protocol itself, such as verification and timeout retransmission.

By implementing system-level planning from interfaces, cables, grounding to wiring, and adopting Eintec's standardized protection and filtering solutions, reliable communication between the frequency converter and the PLC can be achieved in harsh industrial environments.