Voltage transformer (Potential transformer called PT, Voltage transformer also referred VT) and the transformer is very similar, are used to convert the voltage on the line. But converting voltage transformer is intended to supply electric power, and therefore large capacity transformers, are generally in kVA or MVA for the unit; and the purpose of converting the voltage transformer voltage is mainly used for measuring instruments and power protection devices to measure line voltage, power and energy, or to protect valuable equipment lines, motors and transformers fully enclosed transformer when the line fails, the voltage capacity of small high-voltage transformers transformers, generally only a few voltammetry, dozens of VA, not more than one maximum kVA. Electronic Transformers: frequency power sensor is an electronic transformer, variable frequency power sensor through the voltage and current signals inputted AC sampling, then sampling value of the input is connected to the secondary instrument through the transmission system and digital cable, fiber, etc. digital inputs of the second instrument sampled values ??of voltage and current for computing, you can get the voltage rms, current rms, fundamental voltage and fundamental current harmonic voltage and harmonic current, active power, fundamental power, harmonic power and other parameters. [4] transformer voltage and current transformers are divided into two categories voltage transformer, its main role: once the system voltage, current and accurate transmission of information related to the secondary side of the device; the primary high voltage system large current into low voltage (standard value) on the secondary side, a small current (standard value), the apparatus standardized measurements, measuring instruments and relays, miniaturization and reduced insulation requirements for secondary equipment; the two the primary device and the secondary system and the primary system high pressure equipment well isolated electrically, so as to ensure the safety of the secondary equipment and personal electromagnetic inductive voltage transformer _ Huayi Electric Power (Online) _ Kunming transformer from Xi'an Huayi power plant available. Xian Huayi Electric Power Equipment Factory (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. In Huayi Electric Power leadership with the staff warmly welcome all inquiries negotiations to create Huayi electricity better future.