The left pole of the single-phase 2-hole socket is connected to the N wire (zero wire), and the right pole is connected to the L wire (live wire); the left pole of the single-phase three-hole socket is connected to the N wire, the right pole is connected to the L wire, and the middle pole is connected E wire (protective ground wire); the left pole of the three-phase 4-hole socket is connected to the L3 wire (live wire 3), the right pole is connected to the L1 wire (live wire 1), the upper pole is connected to the E wire, and the lower pole is connected to the L2 wire (live wire 2). All household appliances with metal shells use single-phase three-wire power plugs. The three plugs are arranged in a regular three-solution shape. The longest and thickest copper plug above is the earth wire, and the earth wire has a special ground symbol. The two ground wires are the live wire (the symbol letter is "L" Live Wire), the neutral wire (the symbol letter is "N" Neutral wire), and the order is left zero and right fire. If the wire is not wired according to the wire color of the standard specification, the neutral wire and the ground wire are difficult to distinguish. If the power supply has a leakage protector, plug the socket into the electrical appliance. If it trips, it means that the one connected to the neutral wire is actually the ground wire; if it does not trip, it is connected correctly. It is best to use the standard specification wire colors for the application: yellow for A wire, green for B wire, red for C wire, light blue for N wire, and yellow-green for PE wire. In a single-phase lighting circuit, generally yellow is the live wire, blue is the neutral wire, and yellow and green are the ground wire. In some places, red is used for the live wire, black for the power wire for the neutral wire, and yellow and green for the ground wire. Live Wire (English Live Wire) L is generally red or yellow or green Neutral wire (English NEUTRAL) N (Neutral wire) is generally blue Earth wire (English EARTH) E is generally yellow-green or black three-pole power plug, as shown below As shown, the housing of the electrical equipment is connected to the ground end of the three-core power plug through a wire, and this plug needs to be inserted into a three-pole socket.
