The basic principle of zero sequence transformer zero sequence current protection is based on Kirchhoff's current law: any node in the circuit flows into the complex algebra and zero current. In line with the electrical equipment under normal circumstances, each phase current vector and zero, therefore, zero-sequence current transformer secondary winding no signal output, the actuator does not operate. When the vector of each phase ground fault current is not zero when the high voltage transformers, fault current to zero sequence current transformer toroidal magnetic flux generated in the secondary side of the induced voltage zero-sequence current transformer so that the actuator action, driving high voltage transformer tripping device Ganzhou Which is good, switching power supply network, to ground fault protection purposes. DC transformer error measuring method: 1.5 ~ 3V battery to the positive high voltage transformer primary winding L1 Yiyang Which is better connected to the transformer, L2 then negative, the secondary side of the transformer connected milliammeter K1 positive and negative poles K2, wired high-voltage transformer after Hefei Which is good, close to K mA table pointer positive side, opened the milliammeter pointer after a negative bias, indicating that the transformer connected to the battery positive terminal connected to the head and cents An end table is the positive terminal of the same polarity. 1.K1 the same polarity that transformer is minus polarity. Contrary to the above, such as pointers to swing plus polarity. Which high-voltage transformers Ganzhou | high voltage transformers | Huayi electricity provided by Xian Huayi power plant. Xian Huayi power plant (www.xahy.com) strong, credible, in Xi'an high-voltage circuit breakers and other industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Huayi power and you hand into the brilliant, for a better future!