What are ground wires for? When do I need a ground wire?

The ground wire is a wire used to bring current to earth. The role of the ground wire is to ensure that the leakage of electrical appliances in the case of leakage, the leakage current will flow through the ground wire to the ground, because this circuit resistance is particularly low, so when people touch the leakage of electrical appliances, the current will not pass through the human body, but through the ground wire into the ground, which ensures that people will not have the risk of electric shock.

The following metal parts of the electrical installation should be grounded:

1 motors, transformers, electrical appliances, portable or mobile electrical appliances, etc., metal base and shell:

2 electrical equipment drive;

3 metal or reinforced concrete frames of the house and outside the power distribution unit and near the electrically charged part of the metal fence and metal doors;

4 power distribution, control, protection, and protection of electrical appliances, the current will not be through the human body into the ground. p>4 Metal frames and bases of panels (cabinets, boxes) and operating consoles for power distribution, control and protection;

5 Metal shells and accessible cable metal sheathing of connector boxes, terminals and expanders of AC and DC power cables, and steel pipes for threading. Between the steel pipe for threading or between the steel pipe and electrical equipment with metal hose transition. It should be ensured that the grounding of the metal hose section is unobstructed;

6 Cable bridges, brackets and derricks;

7 Power line towers fitted with lightning conductors;

8 Electrical equipment fitted to distribution line poles;

9 Metal towers of overhead power lines without lightning conductors in the ungrounded, arcing coil grounding and high resistance grounding systems in residential areas without asphalt surfaces and reinforced concrete towers;

10 Frames and metal casings of load-bearing electrical equipment;

11 Cases of generator neutral cabinets, generator outlet cabinets, enclosures of enclosing busbars and other exposed metal parts;

12 Grounding terminals of gas-insulated, totally enclosed combined electrical appliances (GIS) casings and metal boxes of box-type transformer substations;

13 The metal casing of electric heating equipment;

14 armored control cable metal sheath;

15 secondary winding of the transformer.