On which end should the CAN bus shield of the edge computing box be grounded?

When using shielded twisted-pair cable for the CAN bus of an edge computing box, the grounding strategy of the shield layer depends on the ground potential difference. If the ground potential difference between devices is small (<1V), double-ended grounding is recommended to provide high-frequency shielding. If the ground potential difference is large, single-ended grounding is recommended to prevent ground loops. In industrial environments, single-ended grounding to signal ground is recommended, along with a common-mode inductor CML4532A-510T and a TVS ESDCANFD24VAPB. A 1nF 2kV Y capacitor can also be connected in series at the shield layer junction to achieve high-frequency grounding and DC isolation. As the main controller, the edge box typically grounds the shield layer at one end on the controller side, leaving the far end floating or grounded via a capacitor. In a test of a project with a CAN bus length of 50m, double-ended grounding resulted in a common-mode current of 4mA. After switching to single-ended grounding, the common-mode current was 0.2mA, and communication had no errors.