Insulator power frequency withstand voltage test
Insulator power frequency withstand voltage test is the most effective and anthorized way to determine anti electricity performance of the insulator. Insulator power frequency withstand voltage test is primarily done on porcelain insulator, glass insulator and composite insulator.
The purpose of the insulator power frequency test is to judge the problem insulator or insulator string by way of voltage distribution measurement method and insulation resistance measurement method.
Insulator power frequency withstand voltage test should perform on each batch for polymer insulator as a routine test, but it is a type test for porcelain insulator.
Insulator power frequency withstand voltage test procedure: when testing, first about 75% of the rated value is applied to the insulator, then increase the voltage by about 2% per second, until it reaches the rated withstand voltage, stay for a minute. If the high voltage insulator has no flashover or puncture, the test is qualified.
Insulator power frequency withstand voltage test attention: If find the following problem when increase the voltage or withstand the voltage, the power should be cut off immediately. The problem includes: overheating, puncture, flashover, abnormal discharge sound, voltmeter needle swings widely, etc. The tested insulator should be put on the low voltage plate piece by piece, and insulator steel pin end should be connected to the high voltage test transformer terminals.