Grounding wire is a direct connection to the earth's line, can also be called the safety return line, when the danger it will be high pressure directly to the earth, is a lifeline.
Household electrical equipment due to poor insulation or use of humid environment, will lead to its shell with a certain static electricity, serious electric shock will occur. In order to avoid the accident can be connected to a wire in the metal casing of the appliance, the other end of the wire into the earth, once the appliance leakage will be grounded to the earth grounding wire will bring the static electricity to the earth to release.
Expanded
1, zero line: in the home electricity, the zero line usually refers to the line from the transformer grounding body, it is connected to the resistance of strict regulations, must be less than or equal to 0.5 ohms, so as to ensure that the normal use of electrical equipment.
2, firewire: is relative to the zero line, usually home electricity is only one of the three-phase electricity, it is 220 volts line voltage, it is through the zero line to form a circuit to make household appliances work.
3, in the line: is the metal shell of electrical equipment and power (generators and transformers) ground wire to do the metal connection up the line, it requires power supply to the electrical equipment in the line fuse or air switch, in the case of a phase of the electrical equipment touching the shell, can be the shortest possible time to disconnect the circuit, so as to protect the equipment and the safety of life.
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