How to isolate the power DTU communication ground from the power ground?

Isolating the DTU communication ground from the power ground requires cutting off the DC path using isolating devices. An isolated DC-DC module is used to power the communication circuit, with an isolation voltage of 3000VDC. Signal isolation uses optocouplers or digital isolators (such as ADuM1410). On the PCB, the communication ground and power ground are physically separated and bridged by isolating devices. The spacing between the separations should be greater than 2mm. For interface cables, shielded twisted-pair cables are used, with the shield grounded at one end on the communication side. The isolation effect is verified through a withstand voltage test (1500VAC/60s). After isolation, the resistance between the two grounds should be greater than 100MΩ. Isolation prevents ground noise coupling and improves communication immunity.