If you want to measure and calculate parameters at voltage levels of 35KV and above, it is easy to think that the equipment you need to use is a line parameter tester, and it is also clear that either a power frequency line parameter tester or a different frequency line parameter tester should be used. This device is often used by power grid personnel to verify positive sequence impedance and capacitance, induced voltage, zero sequence impedance capacitance, etc., so as to determine the parameter values of mutual inductance reactance or coupling capacitance between two different transmission lines. So, is there a difference between the line parameter instruments used by power companies for testing and the line parameter testers used by the power grid? What kind of difference does it make?

Firstly, let's take a look at the general requirements of power companies for line parameter testing equipment? Specifically, the main requirements are as follows: 1. The testing system can perform parameter testing on various high-voltage overhead lines and high-voltage cable lines on site with single-phase power supply conditions. 2. When testing high-voltage transmission lines erected on the same pole and crossing multiple lines, as long as the impedance parameter test and the short-circuit (grounded or ungrounded) on the opposite side of the line are conducted, and the induced current of each phase of the tested line is less than 100A, the power supply of the testing system can output a fixed frequency test power supply for normal parameter testing. The instrument adopts DSP technology and has strong anti-interference ability on the testing site. The testing site instrument automatically tests the positive sequence impedance, zero sequence impedance, positive seat capacitance, zero sequence capacitance, phase current, capacitance, coupling capacitance, mutual inductance impedance and other test data of the high-voltage transmission line. The testing speed is fast, the accuracy is high, the repeatability is good, and the anti-interference ability is strong. 4. The tester has the advantages of clear identification, simple wiring, no need for phase change/inversion testing, fast operation, safety and reliability; To avoid misoperation. 5. The instrument has automatic protection function, with short circuit, overcurrent, and overvoltage alarm prompts to ensure that the instrument is intact and personnel safety in case of abnormal situations. 6. The instrument host can be used as an AC power frequency harmonic parameter tester to test power harmonics of the 1st to 31st order, and can save and print data.

The panel of the current line parameter tester is equipped with three-phase overcurrent and overvoltage protection, which ensures the safety of the equipment and power personnel through insurance protection (and must also follow the high-voltage test safety operating procedures to reliably ground the equipment's grounding terminal).