Transformer voltage and current transformers are divided into two categories. Voltage transformer can be used for voltage and power measurements in high-voltage and high-voltage power system towards. Current transformers can be used in measuring the exchange of current exchange measurements and power lines to protect electrical drag degrees. Welcome to inquire ...... Huayi Electric Power Thank you for your attention! 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 Huzhou high voltage transformer Which is good, therefore, zero-sequence current transformer secondary winding no signal output high voltage transformer Wuhan Which is good, actuators no action. When each phase current ground fault occurs in the vector is not zero Yichang high voltage transformer Which is better, the fault current to zero sequence current transformer toroidal magnetic flux generated in the secondary side of the zero-sequence current transformer induction voltage causes the actuator movement, driven tripping device, switching power supply network, to ground fault protection purposes. Which high-voltage transformer Xiangfan _ Huayi Electric Power (certified) _ Xi'an high-voltage transformers supplied by Huayi power plant. Xian Huayi power plant (www.xahy.com) is a leader in Xi'an, high voltage circuit breakers, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Huayi power in leadership with the staff warmly welcome all inquiries negotiations to create electricity Huayi a better future.