The generator has three phases and four wires (three fires and one zero), and the distribution cabinet has three phases and five wires (three fires and one zero and one ground). After fire to fire and zero to zero, the). The ground wire of the distribution cabinet is directly connected to the ground wire.
If the distribution cabinet and the generator are very close, the distribution cabinet and the generator must share a common ground wire, that is, the generator shell, the shell of the distribution cabinet and the zero line of the generator (neutral). line) are all connected together, the ground wire of the distribution cabinet is taken from the neutral line and the metal shell of the distribution cabinet. There is no need to go to the generator to get it.
If the distribution cabinet is far from the generator, the distribution cabinet must have an earthing body complying with regulations and be connected to the earth wire of the cabinete distribution and the metal shell of the distribution cabinet.
380V/220V low voltage power distribution system can be divided into: IT system, TT system and TN system according to different forms of protective grounding.
The power neutral point of the computer system is isolated from ground or high impedance grounded, while the metal shell of the electrical equipment is directly grounded. That is to say: it used to be called the protective grounding of the three-phase three-wire power system.
The neutral point of the TT system power supply is directly grounded; the metal shell of the electrical equipment is also directly grounded and has nothing to do with the grounding of the neutral point of the power supply. That is, the protective grounding of the previous three-phase four-wire power system.
The TN system, in a network380/220V three-phase four-wire low-voltage electrical outlet where the neutral point of the transformer or generator is directly grounded, connects the metal shell of electrical equipment that is not loaded during normal operation through the line public protection Direct electrical connection to the neutral point of the electrical supply. That is, the protection of the old three-phase four-wire power system was connected to zero.
The neutral point of the TN system power supply is directly grounded and has an exiting neutral wire. According to its protection line form, the TN system is divided into three types: TN-C system, TN-S system and TN-C-S system.
(1) TN-C system (three-phase four-wire system), the neutral line (N) and protection line (PE) of this system are integrated, and this line is also called protected neutral Line line (PEN). Its advantage is that it saves a wire,but its disadvantage is that when the three-phase load is unbalanced or the protective neutral line is disconnected, the metal shell of all electrical equipment will be charged with dangerous voltage.
(2) The TN-S system is a three-phase, five-wire system. The N line and PE line of this system are separated and the five-wire power supply is used from the transformer. . Its advantage is that no current flows through the PE line under normal circumstances, so it will not cause electromagnetic interference to other equipment connected to the PE line. In addition, since the N line is separated from the PE line, disconnecting the N line will not affect the protective effect of the PE line.
③TN-C-S system (three-phase four-wire and three-phase five-wire hybrid system), this system is a four-wire system from the transformer to the user distribution box, and the neutral wire and the neutral wireprotective earth are integrated; The neutral wire and protective earth wire from the distribution box to the user are separated, so it has the characteristics of TN-C system and TN-S system. It is often used in poor environments. at the end of the distribution system or electromagnetic interference requirements in more stringent locations.
How to connect the generator line of a gasoline engine? There are three lines on the generator. How should I connect it?
The generator UVWs each represent the three-phase wiring of the three-phase motor.
The letters on the generator connection terminals represent their respective meanings:
1, B represents the positive output, which is power.
2. E represents mass, which is the negative pole.
3. F+ represents the positive pole of the regulator.
4, F- represents the negative pole of the regulator.
5. D is a pspare part and can be connected to a tachometer, etc.
6, N represents the neutral point extraction joint.
Whether it is a gasoline generator or a diesel generator, the principle and power of the generator are the same.
There are two sets of coils inside the generator. One is an excitation coil, also called a magnetic field coil, which is used to generate a magnetic field after being powered. The other is also an armature coil. called rotor, which is generated by rotating and cutting magnetic lines of force. The circuit diagram of the generator is as follows:
As shown in the circuit diagram, the output line of the generator has three terminals, namely the magnetic field terminal, the voltage output terminal and the earth wire. Terminal.
As shown in the figure, the magnetic field terminal should be connected to the magnetic field of the voltage regulator, and the sovoltage part is connected to the battery and electrical equipment.