Precautions and product characteristics during AC voltage withstand test

The main equipment required for AC voltage withstand test are:

Test transformers, voltage regulation and control equipment, voltage measurement devices, protective resistors, and protective ball gaps.

 Precautions

1、Before the AC voltage withstand test, the external insulation surface of the tested object should be wiped clean. For oil filled equipment, the oil should be kept stationary for a period of time according to regulations to eliminate possible residual air inside

2、The AC withstand voltage test is a destructive test and must be conducted only after all insulation test items have passed the test.

3、During the boosting process, the voltage rises slowly while the current rises sharply, which may be caused by a short circuit or similar situation in the tested equipment, or it may be due to the tested equipment having excessive capacity or approaching resonance.

4、During the boosting process, the current decreases and the voltage remains basically unchanged or shows a downward trend. This may be due to excessive test load and insufficient power capacity. This should be particularly noted when using a long-distance external power supply or a portable generator.

5、Most of the tested objects connected to the test transformer are capacitive. During the AC withstand voltage test, the capacitive current generates leakage reactance voltage drop on the winding, causing the actual voltage value applied to the tested object to exceed the voltage value that should be output on the high-voltage side calculated based on the transformation ratio, resulting in a capacitance rise effect. Therefore, when conducting AC withstand voltage tests on large capacitance test objects, it is required to directly measure the test voltage at the end of the test object to prevent it from being subjected to excessive voltage.

6、Test transformers should generally be used within the specified rated voltage range to avoid being used in the saturated part of the iron core.

Product characteristics

1、Intuitive reading: This instrument adopts a digital LCD meter head, which can directly display the test values of high voltage, instrument voltage, low voltage current, and high voltage current, making it easy to observe and record in experiments.

2、Measurement accuracy: fully digital processing, built-in precision mathematical model, with high measurement accuracy and accurate test values.

3、Accurate protection function: fully digital processing, the setting of overcurrent protection values, timing voltage settings, and overvoltage protection values are all achieved using numbers, making protection more accurate.

4、Automatic timing: The device has a timing trigger function, which automatically timing based on the set voltage value, making the timing more accurate and effective.

5、Safety grounding inspection: The instrument has a safety grounding inspection function. When the instrument is not safely grounded during the test, it is not allowed to conduct a closing test.

6、Convenient to carry: Small in size and light in weight, with a volume only 30% to 70% of that of similar products, making it very convenient to carry.

Kvtester Electronics Technology Co.,Ltd. is a high-tech enterprise specializing in power testing, testing, research and development, production, and sales of testing equipment. It has been engaged in the electrical testing industry for many years, and its products are of high quality. We welcome customers to come and purchase.