Such huge equipment is not only bulky and expensive, but also very inconvenient to use. To solve this problem, the test frequency is reduced, thereby reducing the capacity of the test power supply. Years of theory and practice at home and abroad have proven that the 0.1Hz ultra-low frequency withstand voltage test can replace the power frequency withstand voltage test, not only with equivalent effectiveness, but also with greatly reduced equipment size and weight. The capacity is about one five-hundredth of that of the power frequency, and the test procedure is greatly simplified. Compared with the power frequency test, it has more advantages, which is why developed countries commonly adopt this method. China's Ministry of Electric Power has commissioned the Wuhan High Voltage Research Institute to draft the industry standard "Ultra-low Frequency (0.1Hz) Withstand Voltage Test Method for 35KV and Below Cross-linked Polyethylene Insulated Power Cables". China is promoting this method, and this instrument is developed based on this national need. It can be widely used in AC withstand voltage tests for cables, large high-voltage rotating motors, and power capacitors.
It has power supply overcurrent, high voltage overcurrent, protection functions, and functions such as the high voltage cannot be started if the output voltage regulator is not returned to zero. It is a replacement product for traditional power frequency withstand voltage test equipment. The ultra-low frequency AC withstand voltage device is a new type of ultra-low frequency AC test device that mainly uses sine wave orcosine square wave as the output source. It is mainly used for non-destructive insulation withstand voltage tests of PE (polyethylene)/XLPE (cross-linked polyethylene) plastic power cables in the power sector. It has reached the international advanced level of the late 20th century and the domestic leading level.
1. Output voltage: (KV) 30, 50, 80
2. Output frequency: 0.1Hz, 0.05Hz, 0.02Hz
3. Load capacity: 0.1 Hz max 1.1uF
0.05 Hz max 2.2uF
0.02 Hz max 5.5uF
4. Measurement accuracy: 2.5%
5. Voltage positive and negative peak error: ≤2.5%
6. Voltage waveform distortion: ≤5%
7. Usage conditions: indoor and outdoor; temperature: -10℃∽+40℃; humidity: ≤85%RH
8. Power supply: AC 50 Hz, 220V ±5%
