Three-phase electricity is made up of four wires. Three live wires and one neutral wire. Three-phase alternating current is a form of electrical energy transmission, called three-phase energy. Three-phase AC power is a power supply consisting of three AC potentials with the same frequency, amplitude and phase differences of 120° from each other.
Three-phase alternating current has many uses. Most AC electrical equipment in industry, such as motors, uses three-phase alternating current, which is three-phase alternating current. often The three-phase four-wire system mentioned. In daily life, single-phase power supply, also called lighting power, is mainly used. When lighting electricity is used for power supply, one of the three-phase electricity is used to power equipmentelectrical equipment, such as household appliances, and the other line is the fourth line of the three-phase four-wire, which is the neutral line. . The neutral line is drawn from the neutral point of three-phase electricity.
In the low-voltage distribution network, transmission lines generally adopt a three-phase four-wire system. The three lines represent the three phases A, B and C respectively and are not divided. one is neutral line N (different from neutral line, in the single-phase transmission line entering the user, there are two lines, one is called live line and the other is called neutral line. Under normal circumstances, the neutral line must pass current to form a current loop in the single-phase line. In the three-phase system, the three phases form a circuit of their own, and the neutral line has no current. under normal circumstances), this is what wecalls a three-phase, four-wire system; in the 380 V low voltage distribution network, in order to obtain the 220 V line from the phase-to-phase voltage of 380 V.
The unit of 16 square meters, three-phase , four-wire, three-light and one-zero can carry 6 22Ov3 HP air conditioners.
The 16mm copper wire can support a three-phase, four-wire load of approximately 25 kilowatts. The feeding radius should not exceed 50 meters. The power of 3 air conditioners is 2400 watts, so the 16-. square meter three-phase four-wire three lights and one zero Can carry 6 22Ov3 air conditioners.
Extension: Three alternating currents of equal size, same frequency and initial phase difference of 120° form a three-phase alternating current. Actual three-phase alternating current is generated by a three-phase generator. In the generator there are three identical windings distributed evenly with a spatial difference of 120°. The rotation of the geThe generator can produce three single-phase alternating currents that meet the above conditions. Since the initial phase difference is 120°, there is a time difference in the current flowing through each wire. six wires to provide power, but only inside the generator. Connect the three windings in a certain way and use three or four wires to supply power. The alternating current emitted by each winding of the generator is called one phase of the three-phase alternating current, which is the single-phase alternating current we use.