Testing of Insulator

Testing of Insulator : Electrical insulators are tested to avoid unwanted insulator failure, the electrical insulator must undergo the following tests: 1) Flashover tests of insulator 2) Performance tests 3) Routine tests Flashover test are mainly of three types :- (i) Power frequency dry Flashover Test of insulator : Here insulator to be tested is mounted in a practical manner as it is used on poles and Variable power frequeny voltage source are connected to the insulator. Applied voltage is gradually raised upto minimum flashover voltage. This voltage is maintained for one minute and observe that there should not be any flashover or puncture occurred. It should be capable to sustain at minimum specified voltage for one minute. (ii) Power frequency Wet Flashover Test / Rain Test of Insulator : Here Again the practical condition of insulator is developed with applied variable power frequency voltage source. After that...