What is zero sequence current? -Solutions - Huaqiang Electronic Network

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

Photocoupler

In a three-phase four-wire circuit, the phasor sum of the three-phase current is equal to zero, that is, Ia+Ib+IC=0. If a current transformer is connected to the three-phase four-wire, the induced current is zero. When an electric shock or leakage fault occurs in the circuit, a leakage current flows through the loop. At this time, the three-phase current phasor and unequal zero passing through the transformer are lumped sum: Ia+Ib+Ic=I (leakage) Current) There is an induced voltage in the secondary coil of the transformer, and this voltage is applied to the electronic amplifying circuit of the detecting portion, which is compared with the predetermined operating current value of the protection zone device, such as greater than the operating current, even if the sensitive relay operates, acting on the execution The component is turned off. The transformer connected here is called zero-sequence current transformer, the phasor sum of the three-phase current is not equal to zero, and the generated current is the zero-sequence current.