How to avoid ground loops in the hybrid grounding of intelligent low-voltage monitoring units?

Hybrid grounding avoids ground loops by combining high-frequency multi-point grounding and low-frequency single-point grounding. Digital circuits use multi-point grounding; analog circuits use single-point star grounding. Both are connected via a PBZ1608E600Z0T ferrite bead. The chassis grounding uses single-point grounding. The cable shielding is grounded at the monitoring unit end, and the other end is grounded via a 100nF/2kV capacitor. An isolated ground plane is provided on the PCB. This hybrid grounding minimizes ground loop area and reduces ground loop interference by more than 25dB, meeting the IEC 61000-4-8 power frequency magnetic field immunity test requirements.