Grounding

Connecting the ground terminal of a power device to the earth using a conductor. Grounding plays an important role in safely discharging abnormal voltage to the earth in order to prevent electric shock when a device becomes charged due to a leakage current. Therefore, the grounding resistance, which is the resistance between the ground terminal and the earth, must be low to allow easy flow of current into the earth. According to the technical standards for electrical equipment, for low-voltage devices of 300V or less, grounding resistance must be 100Ω or less (Type D grounding). Grounding is also sometimes used for noise reduction in addition to electric shock prevention.

Related content