# Do you know why the voltage difference between the two phase wires is 380V?

Do you know why the voltage difference between the two phase wires is 380V? First, let’s briefly talk about the line voltage and phase voltage: the line voltage is the voltage between the live wire and the live wire, which is 380V, and the phase voltage is any one of the three live wires. and the voltage between neutral, is 220V;

Do you know why the voltage difference between the two phase wires is 380V? First, let’s briefly talk about the line voltage and phase voltage: the line voltage is the voltage between the live wire and the live wire, which is 380V, and the phase voltage is any one of the three live wires. and the voltage between neutral, is 220V;

The voltages are all used by us after being stepped down by the transformer. The secondary side of the transformer is all star-connected. There are three live wires that are ABC three-phase. Do work at the neutral point and connect to zero, and lead out a zero wire. ; We can clearly see from the voltage vector diagram that the line voltage is √3 times the phase voltage, and the voltage between any two items of A-phase B-phase C-phase drawn from the secondary side of the transformer is 380V, so the voltage between the two live wires is 380V. The voltage between them is 380V;

In addition, the phase voltage is the ground voltage of any one of the three-phase ABC, that is, the voltage to the working zero line. This is the phase voltage. The relationship between it and the line voltage can be seen from the vector diagram. It is a √3 times relationship. That is, the line voltage is √3 times the phase voltage; so the phase voltage is equal to 380% √3=219.4, which is what we often call 220V;

Finally, let me tell you that 220V and 380V are our common names. In fact, the actual voltage fluctuates up and down the two voltage values ​​above. In actual operation, it does not run under the exact values ​​of 220V and 380V.