What is the reason for electrification of DC automobile base?

The reason is that the motor housing is not connected with the protective ground wire.

Cabinet grounding is used to form a good conductive connection between metal parts (cabinet shell, console shell, etc.) that are usually not electrified. ) Ensure the safety of equipment and personnel on the equipment system and the ground, which is a protective grounding.

Grounding the chassis can also prevent static electricity from accumulating. The shell grounding and signal grounding of equipment on board should be set separately, and the shell grounding should be connected to the hull grounding nearby, and the signal grounding should be connected to the grounding cable.

Extended data:

Grounding requirements

(1) The ideal grounding should make the currents of all circuits and equipment flowing through the ground wire not affect each other, that is, a grounding current loop should not be formed to avoid the influence of magnetic field and ground potential difference on circuits and equipment.

(2) The ideal grounding conductor (wire or conductive plane) should be a solid with zero impedance, and any current flowing through the grounding conductor should not produce voltage drop. That is, there is no potential difference between grounding points, or the voltage between grounding points can be ignored compared with the potential of any functional component in the circuit.

(3) The ground plane should be at zero potential as the common potential reference point of all electrical signals in any position of each circuit in the system.

References:

Baidu encyclopedia-land of shells