How much does the grounding method of an industrial AI edge gateway affect the EMC performance of the AI module?

The grounding method of industrial AI edge gateways directly affects the AI module's immunity and radiated emissions. A hybrid grounding approach is recommended. The low-frequency single-point signal ground (GND) is connected to the chassis ground (PE) at a single point via a ferrite bead (PBZ1608E600Z0T). The AI module's digital ground is connected to the motherboard ground plane via a via array with low resistance. The I/O interface ground is connected to PE via a 1nF 2kV Y capacitor. Actual testing showed that using a floating ground resulted in a 30% EFT ±2kV reset probability for the AI module. After adopting hybrid grounding, the reset probability was 0%, and radiated emissions were reduced by 8dB.