When using the micro ammeter of the DC high voltage generator, please pay attention to the following precautions. Unreliable wiring during the test or careless attention to the micro-amp meter of the DC high-voltage generator can easily cause the surrounding objects to discharge during the boost process. When testing capacitive samples, incorrect discharge time and discharge sequence may directly damage the microammeter.
Before using the DC high-voltage generator, you need to carefully check whether there is enough safety distance between the high-voltage output line and other objects, and whether there is enough safety distance between the high-voltage pressure side of the product under test. After the tester completes the test, the voltage of the DC high-voltage generator must be reduced to zero, and the obvious power disconnection point must be disconnected, and then the discharge rod can be used to discharge the test object. The entire discharge process is divided into two parts.
When discharging, the discharge rod should not be in contact with the tested product immediately. The head of the discharge rod should gradually approach the product under test. When there is a certain distance between the air gaps, there will be a hissing sound. When there is no sound, the discharging rod can be directly grounded for discharging. The service life of the microammeter of the DC high voltage generator is directly related to the operation method of the tester. The quality of the wiring and the discharge time are directly related to the life of the microampere.
Microammeter specification configuration of DC high voltage generator:
In the conventional test, the DC leakage test of the zinc oxide arrester is the reference voltage under 1mA current, and the DC leakage test under the 75% reference voltage. The current value is 1000uA. The DC leakage test current value of the cable in the conventional test is even smaller. The microammeter of the DC high-voltage generator usually uses a three-and-a-half-digit liquid crystal display (range: 0-999uA). This range is sufficient for conventional DC leakage test items.
Only when large-capacity cables are often manufactured, a larger ammeter range is required. Since the charging current is relatively large when the cable is pressurized, when choosing a DC high voltage generator or 0-1999.9, it is recommended to choose a four-and-a-half-digit liquid crystal display microammeter (range: 0-19999uA or 0-1999.9uA).