Cascade high-voltage test transformer is composed of several single test transformers. Although a single test transformer has the advantages of low voltage, small capacity and light weight, it is easy to install and transport, but after all, the voltage is limited. If it is manufactured to bear high voltage level, it is not easy to transport. The emergence of the cascade high-voltage test transformer solves this problem. It can not only realize that a single test transformer can form several times higher state after being connected in series, thus realizing the combined use of voltage, but also can be directly separated into several sets of single test transformers for use separately, which is convenient for transportation and handling.
1. Cascade order
It must be noted that the capacity of the primary winding is greater than that of the secondary winding for the cascade high-voltage test transformer, so that the peak voltage of the rated voltage of the two test transformers can be obtained.
2. Prevent discharge
If a high voltage test is required, the grading ring and special anti-corona sleeve shall be used to prevent discharge and corona.
3. The second test transformer shall be padded with an insulating platform
During the series test of the two test transformers, the secondary winding must be padded with insulation support or insulation platform, otherwise the voltage cannot rise. The real monitoring of the voltage should be carried out by sampling a digital high-voltage meter (voltage divider) at the high voltage side, because the impact of the stray capacitance of the tested object on the ground, the voltage measured at the low voltage side has a large error, which cannot reflect the real test voltage at the high voltage side.
4. Ensure consistent polarity
During the high-voltage test, the polarity of the high-voltage winding of the first test transformer must be consistent with that of the low-voltage winding of the second test transformer. Otherwise, the low-voltage winding may be burnt out.
