Grounding resistance is an important parameter used to measure whether the grounding state is good. It is the resistance encountered when the current flows from the grounding device to the ground and then flows through the ground to another grounding body or spreads to a distance. It includes the resistance…

The DC resistance tester is mainly used to test the DC resistance value of high-voltage electrical equipment such as power transformers. It has many characteristics such as fast testing speed, high accuracy, convenience, flexibility, and portability. It has always been a favorite equipment for many power workers, and there are…

The interference sources during the measurement of partial discharge of transformer include the interference of power supply network, interference of various electromagnetic field radiation, poor contact of test circuit, corona at various parts and internal discharge of test equipment, interference of earthing system, and interference of suspended discharge of metal…

The main purpose of transformer no-load test is to measure the no-load current and no-load loss, analyze their variation patterns, discover local or overall defects in the magnetic circuit, and discover winding defects. The precautions for transformer no-load test include:1. The test should be conducted at the rated tap, and…

1. The host cannot find the resonance point.Reason: The system resonance point is outside the output frequency range of the host; System wiring error;The system is not reliably grounded; Open circuit or unreliable connection of high-voltage sampling feedback signal; The test sample has a malfunction.Exclusion method:1) Check the reliability of…

1、 Principle of series resonant voltage withstand test deviceThe series resonant voltage withstand test device is a testing method that utilizes a series resonant circuit to achieve high voltage output. The basic principle is to use a transformer to raise the low voltage to the high voltage value that needs…

The volt ampere characteristic is the relationship between the voltage and current of the secondary winding of a current transformer. If the voltage is adjusted from small to large, and each current corresponding to the applied voltage is drawn in a coordinate system (the voltage is in the vertical coordinate…

For transformers, electromagnetic voltage transformers, etc., the main insulation of the tested object (referring to the insulation between windings to ground, between phases, and between windings of different voltage levels) is often checked by using the test method of obtaining high voltage from secondary pressurization. In addition, the insulation strength…

Measuring the dielectric loss factor is a highly sensitive test item that can detect overall moisture and deterioration of the insulation of power equipment, as well as local cracks in the small volume of tested equipment that are connected or not connected. The test precautions for measuring the dielectric loss…

The breakdown voltage of insulating oil is a measure of its ability to withstand voltage inside electrical equipment without being damaged, and is one of the main means to test the performance of transformer oil. The precautions for measuring the breakdown voltage of insulating oil include:1. The structural type of…