How to connect the shield ground and low voltage ground of the intelligent low voltage monitoring unit?

The shielding ground and low-voltage ground are connected using a combination of capacitive coupling and direct connection. The high-frequency shielding ground is connected to the low-voltage ground via a 100nF/2kV ceramic capacitor. The low-frequency shielding ground is directly connected via a 10Ω/1W resistor. The metal chassis is directly connected to the low-voltage ground with a 4mm² grounding wire. On the PCB, the shielding layer connection points use metal shielding covers. With this connection method, the shielding effectiveness is greater than 35dB@1GHz, the grounding impedance is less than 0.2Ω, and it meets the IEC 60950-1 safety isolation requirements (2500VAC withstand voltage).