Product Details

Product Overview

   According to the national standard ZBK41006—89 for transformers, this is a new type of product produced after improvements. This series of products features small size, light weight, compact structure, complete functions, and ease of use. It is suitable for power, industrial and mining, scientific research and other departments, for power frequency withstand voltage tests and DC leakage tests on various high-voltage electrical equipment, electrical components, and insulating materials. It is an indispensable instrument in high-voltage testing.

Precautions    
1. Test personnel should divide responsibilities clearly, set up a safe distance at the test site, carefully check the grounding of the test object and the test transformer, and assign a dedicated person to monitor safety and observe the status of the test object.
2. The main parts of the test object should be cleaned thoroughly and kept absolutely dry to avoid damage to the test object and errors in test values.
3. For tests on large equipment, generally a no-load test of the test transformer should be conducted first, i.e., raising the voltage to the test voltage without connecting the test object, in order to calibrate the accuracy of the instrument readings and adjust the gap spacing of the discharge ball gap.
4. During the withstand voltage test, the voltage rise speed should not be too fast, and sudden pressurization should be prevented, such as sudden closing when the voltage regulator is not at zero position. Also, sudden power off should be avoided; generally, the voltage regulator should be turned to zero before switching off.
5. During the voltage rise or withstand voltage test, if any abnormal conditions are found, such as: 1. large fluctuations in the voltage and current meter pointers, 2. abnormal sounds from the test object, 3. signs of insulation burning or smoking, the voltage should be immediately reduced, the power cut off, the test stopped, and the cause investigated.
6. When using this product for high-voltage tests, in addition to being familiar with this manual, the relevant national standards and operating procedures must be strictly followed.

2. For DC withstand voltage and leakage tests, the wiring method is shown in Figure 5. Since this is an AC/DC dual-purpose transformer, the short-circuit rod of the high-voltage silicon stack should be pulled out from the bushing to put the transformer in DC output state. Before conducting the DC leakage test, first select the resistance value of the current-limiting resistor (water resistor) based on the requirement that the open-circuit current at the output end during the leakage test does not exceed the maximum rectification current of the high-voltage silicon stack. Then, select the capacitance value of the high-voltage filter capacitor according to the requirements of the DC high-voltage waveform for the test object. To improve the measurement accuracy of the voltage applied to the test object, an FRC resistive-capacitive voltage divider should be connected on the high-voltage side to measure the voltage.