What the function of the wires in the Power strip

In most countries, the home power supply is single-phase electricity, which is transmitted through a wire (phase wire) to the room and passed through another wire (neutral line).Many plugs and receptacles have a third connector (grounding wire) to connect the earth to avoid any leakage of equipment or personnel.

Phase line

Phase line (also known as the fire line, power line, end line or living line) will transmit the ac power from the power source to the power equipment.The voltage varies from country to country, but it can be roughly divided into several fixed combinations.The most common is to extract one phase from the three-phase electricity.Three storeys high, each layer USES one phase to try to divide equally.Some power systems use two wire joints, or two of them from single-phase multiline power supply, and even a three-phase power supply system.

The midline

The neutral line (aka zero line) sends the current back to the power system, and its potential is usually equal to (or close to) the grounding line.The middle line is drawn from the neutral point of three - phase electricity.The neutral point of a three-phase transformer is usually grounded.

If the neutral point is not grounded, some protective devices may not work properly because the system does not have a suitable reference point (earth equipotential).

In Taiwan, the middle line is also called waterline.

Ground wire

Main purpose: grounding

The ground wire is a wire with the earth equipotential, which is used to connect the shell so as not to cause harm to the person.Because of its small resistance to the earth, the majority of current will flow through the smaller wires.

In Hong Kong, the ground is also called waterline, because the former ground is connected directly to the metal pipes