The ground wire, also known as the lightning protection wire, is a wire used to introduce current into the ground; when electrical equipment leaks or the voltage is too high, the current enters the ground through the ground wire.
The wire should use copper wire and be configured according to the electricity capacity. Not too thin. It is recommended that the wire diameter of the air conditioner use 4 square millimeter wires; sockets use 2.5 square millimeter wires; general lighting fixtures use 1.5 square millimeter wires. In addition to passing through the hollow floor slab, wires must be routed through pipes; wires of different voltages, such as lighting wires, telephone and TV wires, cannot be worn in the same pipe; the power socket panel should be the left neutral wire, the right phase wire, and the upper ground wire. Wrong connection; the neutral, phase, and ground wires should be of different colors.
What color is the ground wire
The yellow, green and red colors of the three-phase insulated wire represent the three phases of AC voltage A, B, and C respectively
The 220V mains phase line is the live line, generally red or brown, because these two colors are hot colors. The neutral line is blue or green. Black.
Use yellow and green grounding wires.
Generally, the most commonly used are phase line red, neutral line blue, and ground yellow-green
DC dot red means positive, black is negative
The difference between ground wire and neutral wire:
The ground wire is a protection wire, one end is connected to the earth and the other end is connected to the metal outer part of the electrical appliance. If the electrical appliance leaks, the current will flow directly into the ground from the ground wire, which is safe for people. The neutral wire is the working wire. In single-phase equipment, the current flows from the live wire through the switch to the consumer, and then flows from the consumer through the neutral wire to the generator. Because the live wire, electrical appliances, and neutral wire are series circuits, the current of the live wire and the neutral wire are the same, but the neutral wire is also connected to the earth, so the neutral wire has no voltage to the ground.
(1) The power supply ground wire is the main trunk line after the neutral point of the transformer is grounded. According to the standard, the grounding is repeated every 20-30 meters, which plays a safety protection role in the circuit. When the human body touches electrical equipment with a charged shell, since the contact resistance of the grounding body is much smaller than the resistance of the human body, most of the current enters the earth through the grounding body, and only a small part flows through the human body, which will not cause harm to human life.
(2) The circuit ground wire is mainly used to prevent interference and improve the radiation efficiency of radio waves during circuit design. The ground wire is widely used as a potential reference point to provide a reference potential for the entire circuit. At this time, the ground wire is not necessarily connected to the real earth, but is often connected to one of the input power wires, and its potential has nothing to do with the earth potential. When designing the entire circuit, the ground voltage is 0V to unify the potential of the entire circuit.
(3) The user ground wire is used to connect a single-phase 220V load to carry single-phase current and three-phase unbalanced current.
(4) The working ground wire ensures the reliable operation of electrical equipment under normal and accidental conditions and reduces the neutral point potential drift of the load.
(5) There are grounding and zero protection functions in TN-C TN-C-S.